Anna Daniels
After the Federal Reserve heist, O’Brien goes back to the bar where Donnie works, which we saw several times earlier in the movie. It’s conveniently close to the Federal Reserve and, while he’s there, O’Brien has a realization. Through a series of flashbacks, we see Donnie dutifully taking notes while listening to Federal Reserve workers, security guards, bank employees, and cops blabbing about their jobs after knocking back a few beers.
It’s then that we realize that the Federal Reserve job wasn’t set up by Merriman; it was set up by Donnie, who hired Merriman to be his figurehead. Unbeknownst to Merriman, this also included taking the fall for the plan after Donnie deliberately doubled crossed him so he could get the actual haul of cash away while the cops were distracted dispatching of the rest of the crew.
In the final moments of the film, we flash to Donnie, who now owns a bar in London. Across the street is a diamond exchange, which we can now surmise is both his next target, and possibly the set up for Den of Thieves 2.
Written by: Looper
