New York Assistant District Attorney Howard Malloy is working hard on investigation about a series of murders related to an extremist group.

Daisy Kenyon is a Manhattan commercial artist having an affair with an arrogant and overbearing but successful lawyer and family man named Dan O'Mara. Daisy meets a single man, a war veteran named Peter Lapham, and after a brief and hesitant courtship decides to marry him, although she is still in love with Dan.