Three weeks ago in New York Barton Drake was invited to attend a party given by Senator Ralph Hobart to announce the engagement of his niece Diane Hobart to Mark Russell youthful millionaire. Diane's kid brother Paul turns up after escaping from prison where he was serving a sentence for a murder he didn't commit. Nobody knows she has a jailbird brother not even her fiancé Mark Russell and Paul wants it kept that way. Then when Betty walks in on them she assumes Paul is a past lover and tells Mark that Diane was kissing another man. Paul leaves before his uncle and Mark enter the room and Mark goes after him to find and confront him. Barton Drake becomes involved when body is found murdered and no one will identify him.