You've heard the AMC drama, which returns tonight for season 2, is one of the best new dramas on TV, but you've never seen it? Here's a crash course on who's who and what's what so far, and a preview of what awaits the ''Mad'' men and women now
DON DRAPER (Jon Hamm)
LAST SEASONDon realized the importance of family too late: First his brother hung himself, then his wife and kids left for Thanksgiving without him. UP NEXT Further exploration of Don's work-vs.-life struggle and his dark past. ''There are still a lot of holes in this guy's life,'' says Hamm. ''A lot of gray area.''