Colin Mearns scrapes a living with a business helping people improve their memory but it is not a huge success and his girl-friend wants out. Then a Mr. King turns up, seeking Colin's help. He is agitated and rather bad-tempered, having placed a bag in a left luggage locker at a station but forgotten the details and the combination. Colin is certainly able to help but, unaware that Mr. King is really a safe-cracker who keeps his tools in the bag, unfortunately becomes too curious for his own goo