“Hey, I’m Keanu,” he introduces himself – unnecessarily, of course, and yet very Keanu-ishly. Despite being so famous his surname has long been superfluous, Keanu Reeves has always given the impression of being utterly unaffected by his own celebrity. He is regularly described by his co-stars as “kind” (Winona Ryder) and “humble” (Laurence Fishburne) and it is easier to imagine him walking on the moon than knocking back champagne with other celebrities on a yacht in St Barts. After all, the most famous paparazzi photo ever taken of Reeves was of him sitting alone on a bench, eating a sandwich out of a plastic bag. Hard to imagine Leonardo DiCaprio doing that.

“I’ll sit anywhere you want me to. This OK?” he says, taking a chair and offering me the sofa in the London hotel room where we meet. At just over 6ft, he is taller than I expected – also unusual for an actor – and dressed in a very Keanu outfit of dark shirt and trousers with sturdy boots. Despite being recently announced as the new face of the high fashion label Saint Laurent, Reeves has long been the patron saint of normcore, decades before it became a fashion statement. And I know this all too well because, from 1991–99, I had at least five posters of him on my bedroom walls modelling said look.

Should one ever meet one’s teenage crush? Up until this week, I’d assumed I was long past the point of being starstruck – I’m a 40-year-old woman, for God’s sake! But now here I am, sitting opposite Reeves, now 54, the beard more grizzled than in my posters and the forehead suspiciously smooth, but still, most definitely Keanu. There’s that devastating smile he flashed at Sandra Bullock at the end of Speed, and there he is saying – and this is where I nearly lose all vestiges of professionalism – “Excellent!” while playing air guitar. Listening to the tape of our interview later is not an edifying experience, as I hear myself – Oh, dear God – flirt with Reeves (because, clearly, a heavily pregnant mother of two is the dream woman he’s been waiting for). Happily, my mortifying giggling soon abates, thanks to Reeves’ management of a situation he has presumably had to deal with every day of his life for the past four decades. And as he does, I get an insight into what it takes to be Keanu Reeves.

We are meeting today to discuss his latest film, John Wick: Chapter 3 – Parabellum. It will unquestionably boost the more than $3bn Reeves’ movies have grossed over the years. When he made the first John Wick film in 2014 – directed, as all the Wick films are, by Chad Stahelski, Reeves’ stunt double on the Matrix films – few expected that a movie about a former assassin avenging the killing of his puppy would amount to much. Despite starring in some of the most successful and seminal movies of the past 30 years – from offbeat hits like Bill & Ted’s Excellent Adventure and My Own Private Idaho, to blockbusters like Point Break, Speed and The Matrix – Reeves has been in at least as many damp squibs, including 2013’s 47 Ronin, one of the biggest box office flops of all time. Yet Wick, a stylish, brooding, ultraviolent revenge fantasy, was an unexpected hit with critics and audiences, and is now a mega-million dollar franchise, giving Reeves his first mainstream hits since the Matrix movies.

Part three – sorry, Chapter 3 – is larkier than its two predecessors, including one incredible scene in which Reeves offs some bad guys using an actual horse as a weapon (rest assured: the horse escaped unharmed). As a testament to the success of the franchise, there are more celebrity co-stars, including Halle Berry, and despite the naysayers when it comes to Reeves’ acting, he is terrific as a man still mourning the death of his wife. (She died at the beginning of the first John Wick film, from that terrible terminal disease, Convenient Plot Device.) “We certainly didn’t know when we started on John Wick that it would become like this,” says Reeves. “We’re only getting to tell these stories because of the audience. So thank you.” He salutes me in thanks, as representative of all the Wick audiences. (If you are imagining this is one of the times I giggled at him, you are correct.)

One of the canniest things about the Wick films is how they riff on Reeves’ public image. Once dismissed as an airhead by those who confused the Bill & Ted movies with reality, for the past two decades Reeves has been seen as a melancholic loner. The famous 2010 photo of him on a New York bench sparked what became known as the Sad Keanu meme, but it only struck a chord because the assumption already existed that Reeves – then in a career slump – was, well, a bit sad. Reeves, with polite firmness, denies that this echo is deliberate – “No, no, I don’t think about that” – although it is hard to believe it wasn’t in the film-makers’ minds as they shot endless scenes in John Wick 3 of Sad Keanu wandering alone through rainy New York streets, empty hotel corridors and a desert.

It quickly becomes clear that polite firmness is Reeves’ modus operandi when it comes to nosy questions: he will give the impression of being up for answering anything while, in fact, saying very little, or nothing at all. (Sample exchange. Me: “Was there ever a moment, maybe after Bill & Ted, when people started reacting differently to you and you realised your life had changed?” Him: “Um, no.” Me: “Really?” Him: “No.”) What this distancing tactic might lack in conversational intimacy, it makes up for in shutting down any embarrassing flirtations from women who should know better. You can’t kid yourself you are soulmates with someone who is building such protective walls against you.

So I’m surprised when he volunteers that Wick’s melancholy possibly has a connection to some of the most painful moments in his life. One other big reason the public perception of Reeves shifted from comedy stoner to faintly tragic figure was because, in 1999, his long-term girlfriend, Jennifer Syme, gave birth to their daughter Ava, who was stillborn. The couple broke up soon after, and two years later Syme was killed in a car accident. Reeves has never married, had any other children or even been reliably linked to other romantic partners since. He has also never spoken publicly about their deaths, and who can blame him? But given that the heart of the Wick films is about him mourning a lost love, the resonance is hard to ignore.

“With any character, the way I think about it is, you have the role on the page, you have the vision of the director and you have your life experience,” he says.

Did he bring his experience of bereavement to the role? “Oh yeah, I thought it was one of the foundations of the role for John Wick. I love his grief,” he says, visibly perking up at the subject.

What is it about grief that interests him? “Well, for the character and in life, it’s about the love of the person you’re grieving for, and any time you can keep company with that fire, it is warm. I absolutely relate to that, and I don’t think you ever work through it. Grief and loss, those are things that don’t ever go away. They stay with you.”

Has he been thinking more about the people he has lost as he’s grown older? “I don’t think it’s about getting older. It’s always with you, but like an ebb and flow,” he says.

Anyone in particular? “Lots of people,” he says, bricking those walls right back up.

***

Keanu Reeves was born in Beirut, Lebanon, the son of an English mother and Hawaiian-Chinese father. (His first name, as all Reeves-ologists know, is Hawaiian for “cool breeze over the mountains”.) With his sister Kim, the family moved around the world, from Australia to Manhattan, before finally settling in Toronto when Reeves was six. I reckon you can often spot an adult who moved around a lot as a kid, I tell him. “Oh yeah? How?” he says, intrigued.

They tend to have a sense of detachment, self-sufficiency, maybe loner tendencies and a strong sense of independence, I say. “Yeah, I clinically belong to that. I definitely have a bit of the gypsy in me,” he agrees.

Reeves’ father left the family when Keanu was three, and disappeared entirely from their lives when he was 13. He and his sister had multiple stepfathers.

That’s a pretty hard age for a parent to vanish off the scene, I say. “For sure, I think it’s definitely traumatising. But it’s hard to know how [it affected me] because I don’t know what the other life would have been, you know what I mean?” he says.

Did his father ever contact him again? “Yeah, in the mid-90s, but I didn’t reach back out,” he says.

This was after his father had been convicted for selling heroin? “Yeah, but that wasn’t why I didn’t get in touch!” he laughs.

So why not? “I just didn’t,” he replies, and that’s the end of that. But I can’t help but think of one of my favourite scenes of his, from Ron Howard’s 1989 ensemble comedy Parenthood, in which Reeves’ character muses about paternal figures: “You need a licence to buy a dog, or drive a car. Hell, you need a licence to catch a fish. But they’ll let any butt-reaming asshole be a father.”

Often the class clown at school, Reeves liked sport and loved acting, and got an agent as a teenager after being talent-spotted in a play. He dropped out of high school before graduation. “I feel really fortunate in a way, because I knew what I wanted to do, and a lot of kids that age don’t. But I had a creative ambition and I did it,” he says. After some early television work, Reeves started getting film roles, most notably in the cult 1986 teen drama River’s Edge, followed by Bill & Ted, and from there the work never stopped.

Back in the 1990s, he was the go-to pin-up for all teenagers who wanted a beautiful, gentle and safely asexual boyfriend (hi!). But his acting, if not his looks, has been a more debatable subject. “Is Keanu Reeves a Good Bad Actor or a Bad Good Actor?” a reader wrote in to ask the New York Times’ film critics in 2011 (the answer was, “Neither! A good actor, period”). Writing in the Guardian, self-professed superfan Joe Queenan put him in a small category of actors so beloved they are beyond criticism: “In most of [his best] movies, Keanu plays a character the audience views more with affection than with reverence or idolatry, like a kid brother who has bitten off more than he can chew and may need outside help to survive.”

Today Reeves has a good riposte to the criticism that he doesn’t, or can’t, act. “I certainly never got it from any of the directors I worked with,” he says, checking off some of the most respected in the business, including Bernardo Bertolucci (Little Buddha), Kathryn Bigelow (Point Break), Francis Ford Coppola (Bram Stoker’s Dracula), Stephen Frears (Dangerous Liaisons), Gus Van Sant (My Own Private Idaho) and Richard Linklater (A Scanner Darkly). “It’s not like I went to meet Kenneth Branagh [who directed him in 1993’s Much Ado About Nothing] and he was like, ‘Excellent, dude!’ You know?” He chucks in a little air guitar to boot.

It would have been pretty funny if Branagh had said that, though. “Of course! But the pigeonholing just comes from journalists and, yeah, that happens a lot. I generally don’t read the press but when I do I’m like, ‘Oh, OK, you’re doing that again,’” he says with a shrug.

I’ve never really understood the criticism. OK, he might not have been perfectly cast in Much Ado and acting opposite John Malkovich and Glenn Close in Dangerous Liaisons when he was only 24 was never going to be a fair fight. But he has always been a far more varied actor than the snarkers allow. He proved his superlative comic timing and endearing charisma in Bill & Ted’s Excellent Adventure and, when it comes to drama and sci-fi, no one is better at maintaining an inscrutable blankness. That quality is precisely what has driven so many directors to cast him, often as a messiah-like figure in movies such as Little Buddha, 2005’s Constantine (one of Reeves’ favourites), 1995’s Johnny Mnemonic and, of course, The Matrix. And of all the improbable actors who became action stars in the 1990s – Alec Baldwin, Nicolas Cage – Reeves seemed the most at home in the genre, in the still deliciously enjoyable Point Break and Speed, which he made in between smaller indie fare. So did he do the big movies in order to fund the smaller projects?

“Honestly, I try not to do anything I don’t want to do. But I guess those movies were in reaction to each other. It wasn’t as thought out as, OK, I finished Point Break, so now I’d better play a street prostitute. It was more like, OK, I finished this, now I want to do that,” he says.

“That” refers to 1991’s My Own Private Idaho, in which he and River Phoenix play street hustlers. Reeves had already met Phoenix through the latter’s girlfriend Martha Plimpton, with whom he had worked in Parenthood. The two quickly became friends, and it’s not hard to see why: both were young actors on the rise with a love of music and a pronounced lack of interest in the glitzier, red carpet side of their job. They were the anti-Brat Pack, and Phoenix, along with Alex Winter from Bill & Ted, were, Reeves says, “definitely my closest friends from that era. We shared an artistic sensibility. River was just so down-to-earth, spiritual and a unique artist. Yeah, I miss him,” says Reeves quietly. When Phoenix suggested the two of them make My Own Private Idaho, “I was in right away,” he says.

They had something else in common, a shared experience suggested in the now almost unbearably moving scene where the two sit by a campfire and talk haltingly about their childhoods.

Mike (Phoenix): If I had a normal family, and a good upbringing, then I would have been a well-adjusted person.

Scott (Reeves): Depends on what you call normal.

Mike: Didn’t have a dog, or a normal dad. Anyway, that’s all right. I don’t feel sorry for myself, I feel like I’m, you know, well-adjusted.

Scott: What’s a normal dad?

Phoenix’s dysfunctional childhood, growing up in a rackety family who for a time belonged to the Children of God cult, has been well-documented. Reeves’ was different, but no slouch when it came to potential trauma. Was that another thing that drew them together?

He ponders the question a full 10 seconds. “Certainly our histories played a role in that movie and in that scene. So I’ll say yes to that, yeah,” he says.

Two years after My Own Private Idaho’s release, the actor who desperately wanted to avoid every Hollywood cliche died the most cliched death imaginable, of a drugs overdose on Sunset Boulevard in 1993. Plenty of his contemporaries were also caught out, either self-destructing or becoming victims of their own success. Reeves adamantly refused to do either. When I ask how he avoided falling victim to drug addiction as Phoenix did, he says, as if it were the most obvious thing in the world: “I just wasn’t into that scene.”

It’s hard to tell if he’s being blithe or defiant when he insists he still lives his life totally normally, unaffected by fans. But if Leonardo DiCaprio went into a supermarket, there would be hysteria, I say.

“Yeah, but Leonardo has fame and fans that I don’t have in that way. Definitely. I don’t know what his experiences are, but I think someone from the outside would think [going shopping] might not be easy for him. Whereas I can, which is good,” he says.

Come on, surely fans bother him all the time? But the worst he can come up with is someone quoting Point Break at him in the airport the other day and someone, once, quoting River’s Edge when he was queueing at an ice-cream van. “And that’s fun!” he says cheerfully.

In the 1980s and 1990s, he was offered every hot young part under the sun, including the lead in Platoon (which went to Charlie Sheen) and Val Kilmer’s role in Heat. But when I ask if he regrets turning any of them down, he smiles and instantly replies, “No.” He also turned down a $12m pay cheque to make Speed 2 because he, rightly, thought the plot was nonsense, which resulted in him being shut out of 20th Century Fox films for the next 11 years (and no, he doesn’t regret that, either). He is about to start shooting Bill & Ted Face The Music, in which the now fiftysomething duo have to write a song so good it will save the universe. “There has to be a reason for making a movie, and the writers have come up with a good ‘why’ for telling the story,” he says. When I ask what gives him an ego boost, given that he’s not driven by money or fame, he is so baffled by the idea of his ego needing a boost that he is silent for a full 28 seconds before finally answering, “The work.”

Maintaining his privacy has been a major factor in helping Reeves retain his sanity, yet away from the press he can be extraordinarily open and laid-back. By a weird fluke, I have two friends who, separately, spent time with him in the 90s and both still talk about his generosity: he took them for rides on his motorbike and stayed in touch (yes, I am furious with them for not including me in any of this). There are legions of stories about Reeves’ kindness: buying his stuntmen motorbikes, renegotiating his Matrix contract so that the crew got a better deal, at a personal cost of millions of dollars. Shortly before we meet, Reeves was on a flight between San Francisco and Los Angeles that was grounded due to a mechanical fault. Instead of pulling rank with some “Do you know who I am?” A-list entitlement, Reeves encouraged his fellow passengers to board a van with him so they could drive to LA, keeping the mood up by sharing fun local facts and playing music from his iPhone. (Needless to say, footage of this quickly went viral.) So his four decades-long reticence with the media might well be Reeves’ most brilliantly sustained performance.

But he bristles when I mention these stories. “I’m pretty private, so when that stuff doesn’t stay private it is not great,” he says.

Because he worries it will look like he’s just doing it for show? “No. Because it’s private,” he says with emphasis.

Ah well. I have accepted by this point that we probably won’t ride off together into the sunset on his motorcycle. But if the price of Reeves still being so recognisably Keanu-ish is him retaining a firm grip on his privacy and at least a pretence of normality, that feels like a fair trade-off. I assume doing this interview has been a torturous experience for him, so as we get up to leave I ask how he’d have preferred to spend the afternoon, in a dream scenario.

“Oh, I don’t know. This dream ain’t so bad!” he says, and gives me that full end-of-Speed smile again. And reader, I giggled.

• John Wick: Chapter 3 – Parabellum is in cinemas now.

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