In the Chuck Season 4 DVD, "Chuck" continues its highly entertaining blend of drama, comedy, and romance. Nice guy computer nerd and newly minted CIA agent Chuck Bartkowski (Zachary Levi) is finally teamed, both personally and professionally, with the lovely and deadly CIA agent Sara Walker (Yvonne Strahovski). At the beginning of the Chuck Season 4 DVD, Chuck and best buddy Morgan (Joshua Gomez) search for Chuck's long missing mother Mary Bartkowski (extended cameo by Linda Hamilton), thought to be a rogue agent working for the villainous international arms dealer Alexei Volkov (a superbly over-the-top Timothy Dalton). In a multi-episode sequence, Chuck, Morgan, Sara and the famously gruff NSA agent John Casey (Adam Baldwin) track and eventually confront Mary Bartkowski and Volkov. Mary's loyalties are something of a mystery, especially after she deprives Chuck of the use of the Intersect embedded in his brain, which provides him with his spy skills. Season Four was originally scheduled for 13 episodes, before being extended to a full season. Lucky fans get two season finales. In the first, Team Bartkowski tries to protect Chuck's sister Ellie from the Volkov gang, as she prepares to give birth to her first child with husband Captain Awesome, and as Chuck seeks a quiet moment to propose to the evasive Sara. In the second, Chuck and Sara must escape the revenge of the Volkov family long enough to bring off their own wedding. The steam could easily have gone out of the series after Chuck and Sara finally got together, but the creative team of Josh Schwartz and Chris Fedak keeps finding ways to keep it funny and interesting. Any number of boomer TV series and movie dramas get hilariously ripped off this season, while a parallel storyline has Casey and Morgan as mismatched house mates and agent partners, with Morgan trying to keep secret his relationship with Casey's daughter Alex.