Loud mouthed Barney Maguire is America's champion heavy weight boxer. At Raffles' Club one evening he brags to Raffles and Bunny that he has a trap which would trap the cleverest of Cracksmen. He also insults the noble game of cricket and ridicules his English boxing opponent. This is enough to tempt Raffles into breaking and entering Maguire's premises, but he is unaware of the nature of the trap which awaits him. It is left to Bunny to save the day.
Sir Arthur Rumbold, the pompous Secretary for Home Affairs, announces that he wishes to introduce much tougher penalties for offences against property. Raffles, believing this to be a step back into the dark ages of Botany Bay and transportation for life, is furious and determines to teach Sir Arthur a lesson by burgling his own substantial London home. Announcing to Bunny that the burglary will be an unplanned affair, Raffles goes enthusiastically to work, but it is not long before events start to go drastically wrong.