Kiriko, in her "prison challenge," sets her sights on robbery. She infiltrates the office of black-market money lender Terada Kazuo by offering to work there as a cleaner, thinking that stealing the big amount of cash stashed there and getting arrested would send her to prison. She searches the safe and other likely hiding places for the money, but during her unsuccessful attempts she ends up inadvertently capturing another thief who had come to raid the office, and getting thanked by Kazuo. Will she ultimately consummate her planned theft?