Frank Leone (Sylvester Stallone) is imprisoned in a minimum security jail, as although he has had a chequered past he feels once this term inside is behind him he can settle down with girlfriend Melissa (Darlanne Fluegel) and turn his hand to fixing cars. The prison is so low security that he is able to get day releases from there to meet with her, and with only a few months left on his sentence he's looking forward to a new lease of life - that is until he returns to the building and is almost immediately forced into the back of a van and sent off to a maximum security prison...
But seeing as how Frank is the nicest prisoner who ever lived, who could possibly be mean enough to do that to him? Step forward the warden of the institution, the electric chair-coveting Drumgoole played by Donald Sutherland in one of his easiest jobs as he spent what little screen time he had sneering, leaving the heavy lifting of the abuse of power to the guards and other inmates. Corruption is the theme here, and we have to stick around to witness whether this corrosive atmosphere will drag Frank down to that level, or if he will rise above it and get through what the warden readily describes as hell. Naturally, the bad guy is banking on the latter.
It seems he has a grudge against Frank who made him look stupid when he broke out of his previous jail to see his dying father (see what I mean? Helluva nice guy), making him lose face as well as his job, so now he's out for revenge. Trouble is for Frank that he cannot prove that he is being victimised when there are so many forces of wickedness marshalled against him, and for a while it looks as if he will have to suffer these indignities alone, that is until he manages to gather his own gang around him, including mechanic Frank McRae, dodgy geezer Tom Sizemore, and new kid on the block Larry Romano.
Well, you can guess what happens to the new kid seeing as he's under Frank's care now, or you can if you've ever seen a prison flick before because here was a movie not so keen on bucking any formula. Indeed this is one of those films you could practically write yourself such is its adherence to the most hackneyed aspects of the genre, and at the time it was released it proved to be one of Stallone's many flops, with the only people truly happy with it being the staff and inmates of the prison they shot this at who not only got to appear in front of the camera but saw the production build them an athletics track as thanks.
However, down the years and through a renaissance in interest in the eighties action movie, Lock Up was rediscovered and taken to the hearts of both those who liked manly men acting tough as could be, and manly men acting unintentionally camp as could be. The homoerotic subtext that many like to joke about in these efforts was well to the fore here, and not only in the plentiful scenes of the mostly male cast grappling with each other (there's a grunting-heavy football game which has to be seen to be believed). The men without women setting gives rise to some amusing displays of sublimated affection, most obviously in the car building montage scored to that hyper-masculine declaration of love, Vehicle by the Ides of March, though that was possibly picked for having an automobile-based title. By the time we get to Frank goaded into an escape attempt to save Melissa from being raped, things are so heightened in their silliness that Lock Up wins you over, especially if you like to take a chance on muscular entertainment such as this. Music by Bill Conti.