In answer to one person's review, did you actually watch any of this film? The 3 men were in the diner to rob the place! That was the whole point of the film (and to say any more would reveal too much of the plot).
Yes, they were all English, but that wasn't relevant to the storyline - and at least it gave Michael Chiklis, always a very watchable actor, a chance to do a quite believable London accent. However, why the scriptwriters decided to call one of the villains `Nigel' is beyond me. I can't think of a more unconvincing name for a working-class Brit. Come on Hollywood, get with the times - 'Nigel' is NOT a common name in the UK. Perhaps you believe we all wear bowler hats?
The flashbacks, while perhaps confusing things a little, did help to fill in the missing pieces and bring the whole thing together. There were enough plot twists and action to keep the film moving along right up until the last 10 minutes or so when things went slightly awry.
All-in-all, a good film let down by a poor ending.