Quincy is entertaining a stewardess when a knock comes to the door of his boat. It's a friend of his, Carl Hopwood, who appears to have been beaten badly, but he's unconscious and cannot say what happened to him. Quincy puts him in his official station wagon and takes him to a hospital, but he realizes the man is dead when he arrives and continues on to the morgue and performs an autopsy. The only person who sees him is the night attendant at the morgue.
Quincy then falls asleep on the couch at the morgue. When he awakens the next morning, he discovers the slides and samples he sent to the lab are missing and the body is missing as well! The only person who saw the body besides Quincy, the morgue attendant, is taking a few days off and nobody he lives with - in a set up that looks like it is left over from the hippy commune days - knows where the guy is.
Carl's current live-in girlfriend claims he was alive that morning - he went to work! At work, a "fake" Carl Hopwood is presented and everyone there acts like Quincy is crazy when he calls the man an imposter. Did I mention that the morgue attendant who saw the body turns up dead of a drug overdose? What goes on here? Unfortunately, nothing very interesting it turns out.
If not for the ending I would have given this a nine. It may be the best episode of Quincy ever. I'd recommend it even if the denouement is less than satisfying.