A superb satirist of academic life on both sides of the Atlantic (Small World, 1985; Nice Work, 1989, etc.), Lodge here turns to a subject much hashed over in American fiction: male midlife crisis and the countless trendy therapies it's engendered. Laurence ``Tubby'' Passmore, bald and rotund in his 50s, suffers from a free-floating sense of dread. To all appearances, his life is going rather well: A successful television writer with two grown children, he enjoys a vigorous sex life with his university prof wife, Sally, to whom he's remained loyal for some 30 years. But a nagging unhappiness first manifests itself in a troubling knee injury that even surgery can't cure. This ``Internal Derangement of the Knee'' (a doctor's way of saying ``I Don't Know'') begins to dominate Tubby's consciousness, setting off his obsessive fears of impotence, his zombie-like behavior at home, and a strange identification with Kierkegaard's life and philosophy. With his long-running TV series in jeopardy, Tubby also provokes his wife into a separation. When things take this considerable turn for the worse, Lodge begins to let loose. Tubby's jealous rage, his fumbling sexual adventures, his pathetic effort to develop a new series on his favorite Danish philosopher--all make for hilarious set pieces. Tubby's various therapies also provide some good fun: his acupuncture, his aroma therapy, his physiotherapy, his cognitive behaviorist, as well as his formerly ``Platonic mistress,'' Amy, a brassy divorcÇe who confirms her own dislike of sex. Finally, Tubby finds peace by delving deep into his past; he tries to atone for his poor behavior toward his first love, an Irish Catholic beauty named Maureen. Tracking her down in the present, he joins her on a religious pilgrimage in Spain: a spiritual journey that crystallizes his own sense of religion as understood from--who else?--Kierkegaard. The decidedly untrendy ending--personal healing through a leap of faith--redeems an otherwise commonplace novel, one more reminiscent of Lodge's earlier fiction about Catholicism and the sexual revolution.