Eddie Arlette is a detective with the New York City police force. While working on a drug case, Eddie tracked down certain criminals. When the police raided, the criminals got away. A tip leads Eddie to believe that at least some of these criminals fled to London, England. Eddie is assigned to head off to London to try to help the London police track down the criminals. Right before he is to leave, though, Eddie finds himself in charge of a particular dog. Out of time and out of options, Eddie takes the dog with him to England, at which point the dog is impounded by the Customs service.
Superintendent Nathanial Jonhnson (Colin Salmon) is reluctant to allow Eddie to wander the streets of London looking for the criminals, but he is willing to allow him out on the streets, if he goes with a London police officer. Eddie is teamed up with Monty Pipin (Julian Rhind-Tutt).
Eddie spends his nights in a rented apartment in London. Oddly enough, though, the daughter of the owner shows up and attempts to live in that apartment. Fiona Bickerton (Sienna Miller) is supposed to be off at school, but has instead dropped out and intends to live in that particular flat in London.