Even though shooting has begun and we've figured out that whole "Who is the villain?" question, mysteries remain about Iron Man 2. Clark Gregg and Kate Mara have both been cast in the sequel, and while Gregg will be returning as Agent Phil Coulson, Mara's role, according to THR, is being kept top secret.

Y'hear that? Top secret, y'all! Meaning we'll probably see set photos in a few weeks that get the fanboys all a twitter, while people like me have to ask "Wait, who is that?" and grumble that we hate doing required reading for movies that don't even exist yet. Or is that just me? Mara, for reference's sake, played Shari on five episodes of 24 back in the day, and has also had roles in movies like We Are Marshall, Transsiberian and Brokeback Mountain.