In his first published novel, St. Louisan Jeffrey Penn May sends a couple on vacation in the Canadian wilderness to evaluate their disintegrating marriage. When the camping trip ends, they expect to return to their St. Louis home either with a repaired marriage or to start divorce proceedings.

But a wilderness accident while paddling on a roiling river separates Susan and David. While each tries to swim to safety, neither knows where the other has gone. After reaching shore, Susan wonders whether her husband has drowned; he wonders the same about her.

As the plot unfolds, Susan reaches the reasonable conclusion that David is dead. David, on the other hand, learns that Susan is alive. Instead of contacting her, he decides to run away from his old life, relocate to the isolated Wyoming countryside and start over, telling no one.

Discussing the plot further would spoil the suspense, so suffice it to say that the journey to the end of the novel is never boring. May is a writer who has dreamed of publishing a full-length novel for decades and persevered through careers as a schoolteacher, compiler of manuals for fighter jets, consultant for a theater company, outdoor guide and fly fisherman.

The scenes set in rural Wyoming feature the geography as much as the characters. Locales in Canada and Mexico also figure into the plot. Still, the story keeps coming back to St. Louis, which should add to its appeal for local readers.

Steve Weinberg of Columbia, Mo., reviews books regularly for the Post-Dispatch.