In the second season, the team learns about rogue spies engaging a war in the government and are trying to build their own intersect. We also learn about Chuck's father and how he is involved with everything. By the end of the season Chuck's sister Elle is planning her wedding to Captain Awesome. :) And a new intersect for the government is finished.
In the current season, Chuck trains to become a real spy because of the new intersect being destroyed and once again entering his brain. Chuck can now take on "powers" or learn new things like kung-fu or fencing just by flashing on a weapon or a stance. He also has to face his feelings for Agent Walker and she tries to deal with her feelings for him as well.
So if you need something funny, exciting and suspenseful to watch, I highly recommend Chuck. Watch it on NBC Mondays 7pm Arizona time, right before Heroes!