Young and restless Nick Adams, the only son of a domineering mother and a weak but noble doctor father, leaves his rural Michigan home to embark on an eventful cross-country journey. He is touched and affected by his encounters with a punch-drunk ex-boxer, a sympathetic telegrapher, and an alcoholic advanceman for a burlesque show. After failing to get a job as reporter in New York, he enlists in the Italian army during World War I as an ambulance driver. His camaraderie with fellow soldiers and a romance with a nurse he meets after being wounded propel him to manhood.
Against the counsel of his friends, psychiatrist Dick Diver marries Nicole Warren, a beautiful but unstable young woman from a moneyed family. Thoroughly enraptured, he forsakes his career in medicine for life as a playboy, until one day Dick is charmed by Rosemary Hoyt, an American traveling abroad. The thought of Dick possibly being attracted to someone else sends Nicole on an emotional downward spiral that threatens to consume them both.
