The impious comedy is about a family of well to do crooks who are shocked when the son, an excellent forger, quits the fold to go straight. The reason is not long hidden: he has met a girl. He takes a job in a bank (his forged references are excellent).

The family makes every effort to get him back into his ancestral profession to no avail until it is discovered that his fiancee, the daughter of a Scotland Yard inspector, is a first class safe breaker. The white sheep is happy to reenter the fold and the family welcomes their talented new daughter in law. Half the fun of the play is the way in which the family rationalize their trade on the basis of free enterprise economics.