The G.I. Joe sequel has officially started shooting, and Dwayne Johnson is already busy tweeting photos of himself as the character Roadblock from the set, where it's currently 110 degrees. Directed by Jon Chu (Fast Five), G.I. Joe: Retaliation stars Channing Tatum (Duke), Bruce Willis (Original Joe), Adrianne Palicki (Lady Jaye), Ray Stevenson (Firefly), Ray Park (Snake Eyes), Arnold Vosloo (Zartan), Elodie Yung (Jinx), D.J. Cotrona (Flint), Byung-hun Lee (Storm Shadow) and RZA (Blind Master). The sequel is set to hit theaters on June 29th, 2012.