Here is the bruised-plum role that put Jack Nicholson into the biggest of big leagues: the role that Kirk Douglas created for the original Broadway version and once coveted for the movie he helped develop – but it’s the part that arguably put Nicholson on the career path to ham craziness.

Miloš Forman’s 1975 version of Ken Kesey’s novel is back on cinema rerelease and Nicholson is Mac McMurphy, the subversive wildman and incorrigible troublemaker, sent down for statutory rape, whose unstable behaviour gets him a transfer to what he clearly thinks will be the cushy option of the mental institution.

All too late, Mac discovers that the set term of his prison sentence has been changed to an open-ended incarceration, dependent on psychiatric assessment. So Mac leads a revolt against the spirit-crushing regime of pills and electroconvulsive treatment and against the icy control of Nurse Ratched (Louise Fletcher). He is the sacrificial holy fool who at one stage leads a breakout, commandeering a bus, like Kesey’s own Merry Pranksters.

The setting is the early 1960s, and the film resembles prison classics from that time like The Great Escape and Cool Hand Luke. Yet the mood is from a later era. The hospital symbolises the repressive madhouse of square society: like Michel Foucault or RD Laing, Mac says his fellow patients are “no crazier than the average asshole around on the street” and, like a Vietnam draft-card burner, Mac fantasises about escape to Canada. Would he be diagnosed as bipolar now?

Watching this again, I am less inclined to regard Nurse Ratched as a simple villain, despite her vindictive humiliation of poor, shy Billy, and more like a professional who refuses to be bullied by a bunch of men. The often forgotten case-study scene shows her to be thoughtful and caring: her subdued, accessibly real performance stands up as well as Nicholson’s fireworks.