First diverting, then increasingly foolish: a strange little psycho-suspense item about slimy, second-rate academic Martin Lockwood, who's desperately trying to Finish up his patched-together Ph.D. thesis on clinical depression. And, though he has happily abandoned whiny wife Beatrice for adoring live-in mistress Helen, Martin himself is succumbing to depression: his research (interviews with depressives) is a disaster; he has writer's block. Then, however, one of the interviewees--a cheeky young ex-student named Ruth Ledbetter--shows up one middle-of-the-night, offering to help Martin with the paper: she has a theory about depression (it's caused by someone close to the victim, a ""parasite person""), and she's soon gathering dramatic research to support it! But is Ruth also responsible for a rash of sudden deaths among Martin's interview subjects? And is she perhaps faking her research results? Well, the upshot is murky and disappointing: Helen near-fatally becomes one of Ruth's victims--leading Martin to an instant personality change on the last page. And, though Fremlin's talent for semi-comic domestic ugliness is on occasional display here, this most often reads like a whimsical short-story idea gone astray--with a choppy plot, unlikely behavior, and unpleasant people.