A nifty science fiction adventure, all the better for reading like a realistic novel. The hero is Luke, the physics student who helped brilliant Tom Humboldt with the time reversal machine in Time Piper (1979). Now Luke is at Cambridge, where two members of Tom's Institute come to enlist him for a further experiment. Young as he is, Luke will command the scientists on a submarine in the Mediterranean while, back in London, leader Tom will ""push the buttons."" But first Luke attends the wedding of two of the scientists, Mary and Arthur; witnesses Mary's odd episodes of terror and blackout, and worries about the rightness of the marriage. On the ship the same low-keyed attention is given to the men, the educated and helpful captain, the claustrophobic life on board a sub--so that as the countdown for the rime explosion progresses it seems as realistic as a NASA operation or a World War II action. The rime breakthrough occurs, successfully and tumultuously. But when it's over, Arthur has been washed overboard. During two hours of searching a man is hauled from the sea, but it's not Arthur. Terrified, crudely dressed, praying in a strange tongue, he has clearly drifted over from an ancient rime and must be returned. When he is, there is Arthur waiting on shore . . . having realized that the other man is Jonah and the sub his whale, and thus figured from the Bible just where he will emerge in three days' rime. This isn't the end of Arthur's problems: The experience gives him amnesia which is only cured months later when Luke and Mary take him to the museum whale, site of Mary's first spell (clearly now a premonition) in the novel's opening scene. This satisfying full-circle closing is typical of Huddy's expert plotting. By focusing on the textures and relationships of the human story and by saving the Jonah connection to spring well along in the novel, she hooks and delights an audience wider than the usual time-machine buffs.