BIOLOGICAL TIME CLOCK is the story of a young woman (Evelyn) who comes to the mythic French Quarter of New Orleans in the 1960’s with a sense of romantic readiness. As she ambles along in the intermittent shadows beneath the wrought iron grill work overhead, she watches the jazz musicians just coming out of the all-night clubs, smelling of sweat, bourbon, and aftershave. They are virile and magnetic even after their all-night gigs. One of them gives her a wink and a grin. She surprises herself when she is tempted to take him up on it, but averts her glance and moves on.
A teenage black prostitute and her madam are having breakfast at a sidewalk table and are in a heated conversation. Evelyn takes a table next to them and listens as she sips her coffee. Reba (the madam) is fat, encrusted with gaudy jewelry, smoking a cigarette in a long holder. Reba has found an apartment in an ornate 19th century boarding house and is trying to talk Ireney (slim, beautiful, 18) into moving in up the hall from her (like the rest of the girls in Reba’s stable). Ireney is playing with her pet lemur (Fobo) and feeding him fruit from her plate. Ireney is indifferent at first, but finally follows Reba to the boarding house and checks in.
Evelyn follows them and also takes up residence there. It is a bit run down, but is richly decorated in the Ars Nouveau style and is loaded with ambiance. At night, Evelyn listens to the jazz band from the club across the street as the rain pelts the palm fronds in the courtyard behind the boarding house. A ceiling fan whirs overhead. The aroma of gardenias fills the air. While lovemaking goes on in the rooms around her, Evelyn feels even more alone and hungry for affection.
Evelyn become friends with Ireney (who wants to be an actress). Ireney has nearly saved enough as a prostitute to go to Hollywood. Ireney survives her squalid and dangerous life on pills and liquor (and some say heroine). Evelyn feels for Ireney, but soon gives her little attention because Evelyn has become obsessed with Clevis Detwyler.
Clevis is a man she saw only once in the the fog and flirted with once on the landing. He is sensual, but secretive, making him even more enticing. Finally they meet again and soon become seriously envolved. Then Clevis leaves suddenly without telling anyone where he is going. Evelyn is thrown into a paroxysm of anguish, spending long periods drunk among the tombs.
On her return one afternoon, a funeral march is going down the street. Reba tearfully tells Evelyn that Ireney has committed suicide. Evelyn is gripped with guilt for forsaking Ireney when she might have helped her. Later it occurs to Evelyn that Ireney may have been murdered. When Evelyn attempts to discover the murderer, there are a series of subtle threats on her own life and a brush with voodoo.
At the end, Clevis leaves a note at the desk for Evelyn to meet him at the depot and marry him. She packs hurriedly to go (now in possession of Ireney’s lemur and a cat). But before leaving, Evelyn is assaulted by Ireney’s murderer and narrowly escapes with her life. Evelyn is madly in love and leaves without reporting the mureder. She has what she has come for.