Lock Up is made in the same, simplistic vein as most other Sylvester Stallone pics – putting him, the blue-collar protagonist, against the odds over which he ultimately prevails.
Emotional guy that he is, Stallone couldn’t wait for his six-month prison term to be up because in the meantime his foster father may die, so he escapes to see him one last time. It seems his cold-hearted warden (Donald Sutherland) wouldn’t allow him a supervised furlough to make the trip.
As revealed through the monosyllabic posturing, Sutherland is the vengeful, sadistic type.
The rest of the film is Stallone trying to survive ‘hell’ that Sutherland, as the Devil, has diabolically allowed to run amok.
Short of ordering, ‘kill, kill,’ Sutherland allows certain of his uniformed henchmen backed up by lifer prisoner/ringleader Chink (Sonny Landham) to bring Stallone down.
Darlanne Fluegel, as his faithful girlfriend, shows up occasionally to present the soft side of things but her character’s only interesting attribute is that she’s not a man.