I went nuts for The Thieves when I saw it last year, to the point that I promoted and hosted a Tugg On-Demand screening of it here in Austin. The trailer makes it look like an Ocean's Eleven (2001) ripoff, but it isn't, setting aside the fact that they borrow some music and style cues for the heist portion of the movie. About 80 minutes in, it spins into a Hong Kong action caper.
The Thieves was the biggest box office hit in South Korea's history, it has a Korean/Hong Kong hybrid cast to die for, and it's probably not on the radar of most. It's one of my go-to blind recommendations at the moment.
It's now on Blu-ray for a mere $13 (the cost of a single ticket to the movies in many areas), and you can rent it in iTunes now as well ($3/$5 for SD/HD).