I was on the set of a television drama that aired recently, and during a break in the filming I gravitated towards the table of refreshments. It was a cold spring day, and the hot coffee and biscuits beckoned me towards them, not to mention the oversized bakewell tarts and miniature packs of Haribo sweets. As I reached this sticky oasis however, I was duly informed that these treats were reserved for the “talent” – the real actors – and was directed towards the refreshments dedicated to the background artists. This rickety table boasted a large urn of hot water, some sugar packets, and nothing else. I tell this tale not just to grumble, but because it pretty accurately sums up the stark cultural divide, the yawning chasm of respect that exists between the all-star cast and the little people in the background.

Being referred to on set by our technical name of “supporting artistes” (SA) is to make us feel more important, I suppose. “Walking background” and “human props” are two of the gentle and tired jokes used to describe the role of the film and television extra, usually by extras themselves, but the description is entirely appropriate.

Extras aren’t supposed to say anything during a take, for as the saying goes, you aren’t being paid to talk. Nor are you allowed to talk between takes when everything is being reset and put back to the way it was two minutes before. A gentle murmur of conversation will inevitably well up among some groups, at which point one of the assistant directors will immediately bellow for silence, even while the actors are still loudly laughing and singing, or in the case of one particular actor, emitting little shrieks and mewling noises for her own entertainment.

There are many other rules that must also be obeyed and failing to do so could result in you being immediately fired and forever blacklisted from the industry. Your contract specifically orders you not to talk to any of the actors, much as you are advised not to feed animals in a zoo. On one production I was introduced to the lead actor and told what my role would be in that particular scene. I smiled at him in a mild attempt at camaraderie and he stared right through me, as though trying to see his own reflection in my eyes. Until that day I had never known someone to literally look down their nose at me, but when the lead actress was brought out, the expression on her face expressed quite clearly that she had decided not to make an effort with me. You’d have thought she might try to act a little to cover it up.

When I first signed up to be an extra, I saw it as an interesting way of earning a second income, but the pay is so bad that after a couple of jobs you soon come to accept it as little more than a hobby. The average shoot pays about £100 a day, but after tax and agency fees you’re left with half of that, if you’re lucky, and that’s not counting what you spend in petrol or train fares to get to each location.

Some people try to make a living out of being an extra. But any work that comes up is generally very last minute, and it is hard to fit in between the demands of a family. There are times when you do get caught up in the moment, when you’re picked out to play a more substantial part in one scene, and you feel as if maybe the invisible divide between actor and extra isn’t so insurmountable after all; but when you’re finally released to go home at two o’clock in the morning after walking up and down a quayside 50 times, your head weighed down by a tin helmet, and the actors still have hours more to go, the job doesn’t seem quite so glamorous and you feel a little less begrudging about how much more they earn than you.

Weather conditions tend to be either insufferably hot or unbearably cold. After spending an entire afternoon in March in the grounds of a castle ruins, I was barely able to make my misshapen claw of a hand sign my release form at the end of the day. Night shoots are the worst for this, although the extra money you receive almost makes up for it.

On the set of a blockbuster, a mix-up in the costume department resulted in me spending two nights in an aircraft hangar, drinking terrible coffee and reading Maigret books while the other SAs all ran around outside in the freezing drizzle with fogged-up goggles, tripping over railway tracks and trying not to fall on their own rifles. Every time they trudged back in from a take they looked so tired and dejected it was like they had just returned from actual war. Everybody received £500 for their pains, but while for some people these pains took the form of knocked-out teeth and minor injuries, my biggest discomfort was sitting too close to the portable heater.

The best aspect of the work is the free catering: getting up at 4am isn’t so bad when you can go straight in for coffee and a full English, and lunch almost always involves some sort of sponge pudding with custard. Obviously you aren’t allowed to eat anything before the “talent” and the crew, so inevitably you step aside while a never-ending queue of actors and cameramen forms ahead of you. Likewise when trays of sandwiches and cakes are brought on to set during a particularly long shoot, you stand and stare like street urchins while some guys wearing production bomber jackets pick and graze at the aluminium trough first.

For period dramas you also get the added benefit of a free haircut and shave, although this can make things awkward if you’ve had to phone in “sick” at your day job, and then turn up the next morning looking like you’ve just stepped out of a Messerschmitt.

Then there is the faint thrill of seeing yourself on screen as a blurry outline to one side or a tiny figure off in the distance. The only people who really pay any attention to extras on TV are other extras, and even then you’re still unlikely to spot anyone you’ve worked with. But then that’s what extras are supposed to do: to blend into the background and not divert attention from the main characters.

Would I recommend becoming an extra? In terms of taking it up as a serious endeavour to make money or an attempt to crack into the industry, probably not. Every time I sign up for something I always feel a faint sense of impending doom, and I have yet to actually watch anything I’ve been in all the way through. If, however, you like the idea of dressing up in a velvet suit on a hot summer’s day and spending all afternoon in a room full of candles in order to be able to glimpse yourself on the big screen for maybe three seconds and tell your family and friends how you’ve seen [insert random A-lister] up close eating vol-au-vents, then apply now.