Stirlling Silliphant was in a strange mood when he penned this one-off episode, which begins suspensefully with James Franciscus' wife committing him in a comatose state into a mental hospital on Welfare Island (which was renamed Roosevelt Island 15 years after this show was filmed). We soon learn he's going undercover to find the murderer who just offed a witness in a mob case who was incarcerated in that ward.
An interesting premise here is that the killer is actually the only sane guy in the ward -the real mental patients are relatively harmless -this inversion of conventional wisdom conforms to the reality that unlike the prejudice that the mentally ill are the key reason for mass killings that currently permeate our headlines, in fact the mentally ill are more likely to be victims than victimizers.
Franciscus does a fine job pretending to be sick (and violent) until the patients find a photo in his visiting wife's purse that tags him as a cop instead. Before they can gang up on him and kill him he figures out who the real killer is, making for a photogenic chase on location at the Queensborough Bridge leading to some phony sentimentality at the end. Among the nuts in the cast is a very young Donald Moffat, fun to see in his first credited screen role.