Recently paroled convicts Herbie Haseler and Marty Miller are broke and go to New York to get funding for a planned heist from crime boss Nick Marco. Nick is tired of these two idiots who bungled their last caper and Nick is reluctant to finance Herbie and Marty again. Besides, the duo still owes ten thousand dollars compounded over the 5 years at 100% to Nick for bankrolling the armored car heist that went wrong, sending Herbie and Marty to prison. However, Herbie has been in charge of the prison library and has studied a lot. He convinces Nick to finance one more caper, this time in England, where many rich lords live in opulent mansions. These English mansions house many treasures, including fine art, priceless paintings, antiquities and more. Although skeptical, New York mob boss Nick Marco reluctantly agrees to send Herbie and Marty to England to add some rare paintings to his collection. Nick also gets in touch with his mob contacts in the UK to assist Herbie and Marty. The contact is Frank Finley, the London mob boss who owns most of the London casinos. The target is the large English countryside estate of elderly Lady Sophie Fitzmore who lives with her loyal nephew Freddie Fritzmore. When the crooks get on site the caper doesn't go as planned.