The Comic Possibilities of Mid-Life Crisis : IMAGO A Modern Comedy of Manners <i> by James McClure (Penzler Books: $15.95; 244 pp.) </i>

Tom Lockhart is a physician, a diagnostic radiologist, to be precise, who is swept along in a passionate middle-age hormonal reawakening in this story subtitled “A Modern Comedy of Manners.”

The main sense in which this is a comedy is that it would be absurd to take it seriously although calamity and grief are just beyond the edges of every scene.

For example, a sick little girl dies before her defective heart can be repaired. The writing about this tragedy is touching and realistic, and yet the child’s death becomes just an anecdote in the turbulent “big issue”--Tom’s love life. He suffers from a fervent desire to instigate an affair with beautiful 19-year-old Ginny.

Part of his fantasy involves an artwork, “Imago,” that he is sure is an abstract Ginny in the nude. Or it could be merely an abstract tree, as Tom’s wife Sylvia believes. She accuses Tom of seeing only the images of reality, in life as well as in his work.

Sylvia is seen mainly through Tom’s eyes, and he’s not that interested anymore, but the author hints that there’s a real person behind that facade. Tom’s partner, Geoff, has a multitude of problems and misapprehensions, but one is also left puzzling over them while wading through the minutiae of Tom’s imagined passion.

Tom has a devil of a time taking anything seriously except for the young beauty. So dedicated is the befuddled physician to his fantasy that the reader is drawn into it as well. Will she or won’t she? Does she love him too, or is she playing him for an old fool?

Here is a man, about 40, who has just noticed that his physique is no longer hanging together properly. “He looked down, aghast, to see his midriff protruding . . . and suddenly, he felt deeply ashamed of his body.”

Events unfold in a scattered way, and for no apparent reason, Tom decides to have a sexual romp with a cuddly slut named Carole. He even makes plans to move in with her, although he’s still pursuing the enchanting Ginny.

To further complicate matters, there’s Felicity, a brainy colleague at the radiology lab who really understands Tom. No one else possibly could, not himself, not Sylvia, certainly not the reader. Lost in the shuffle is any sense of purpose or plot; it’s all quite cheerful but decidedly pointless.

While the goings-on seem heavy for a comedy, however farcical, the point of view is certainly too silly for anything else. But maybe this is, after all, the proper perspective on the male midlife crisis.