Two of the giants in NFL coaching come together for a film that may answer questions you never knew you had.

ESPN has put out a teaser trailer for the upcoming 30 for 30, The Two Bills, which explores the complicated relationship between Bill Parcells and Bill Belichick, who famously served as Parcells' assistant with the Giants and Patriots before taking over in New England and patrolling the sidelines during one of the league's most impressive dynasties that has resulted in five Super Bowl titles since 2002 (as well as two other appearances).

It's hard to fathom now, but there was a time when Belichick was the understudy to Parcells, who coached the Giants to a pair of Super Bowl titles during his tenure with the G-Men. It's odd to think that Belichick had to learn from the master, considering how he's grown into perhaps the greatest coach in NFL history (although many who cite Deflategate would beg to differ).

Check out the trailer below and get psyched. The Two Bills premieres sometime this coming winter.