The team barely makes it back from the latest heist (where they have raided a truck in broad daylight disguised as nuns) and after a trip to see his old man, Doug has decided he wants to quit and tells his best mate Jem, who isn't too happy.
Doug meets with Fergie (Pete Postlethwaite) to decline the job - and learns that Doug's dad also tried to get out many years earlier, so Fergie got his mother hooked on jobs and she committed suicide. Fergie threatens Claire, so Doug takes some crack himself and then agrees to this last job.
Their raid is going to be at the home of the Red Sox - Fenway Park. Meanwhile the Feds are squeezing Krista for info, using her jealousy as a weapon. Doug and Jem play dress-up as cops and gain access to the stadium with the help of a man on the inside. They get to the money room, tie up the guards, and pack the cash into an ambulance and change into a paramedics uniform.
Jem thought he saw something - and sure enough a team of Feds are waiting outside with some SWAT guys prowling around the stadium car park looking for them. There's a huge gun fight, and the young guy on the team is killed. The fat guy makes a run for it in the ambulance, but is soon shot. Doug and Jem get back in their cop outfits and blend in with the teams looking around the stadium, and get out to the street.
The main Fed guy (not the bloke from Lost) is wise to this fairly basic plan, and follows the only cop walking away from the crime area - with a holdall packed with Swag on his back. They surround Jem, who goes down fighting and is shot by pretty much every officer in the vicinity.
Doug watches, and then makes his escape - in the other direction, in a squad car.
First he calls by the florists - shoots the curly shop keeper, and then murders Fergie. He calls Claire, knowing that she is with the Feds, who urges him to come over -- but then in a change of heart warns him cryptically at the end of the call. Doug again changes into a new uniform, buries the loot, and then gets out of Dodge.
While Claire is tendering to her cabbages, she finds the cash and a note. She uses the money to refurbish the local ice rink, dedicating it to Doug's mum.