Chuck and Morgan try to find Chuck's mother, while Sarah and Casey investigate a Russian operative.

Chuck and Sarah go undercover in Milan in order to find a secret weapon.

Chuck and Sarah's romantic mission is cancelled with the arrival of Hugo Panzer and Heather Chandler. But Chuck grows more interested when the manipulative Heather claims to know a secret about his mom. Meanwhile, as Morgan prepares the Buy More for a huge video game release, he gets a surprise from Big Mike.

Three former buddies of Casey's have gone rogue and look for him.

When Casey's former team returns looking for him, Chuck must decide what he's willing to sacrifice in order to find his mom. Elsewhere, Morgan works up the nerve to reveal a potentially dangerous secret to Casey.

Chuck, Sarah, Casey and Morgan are sent on a mission to stop Dr. Stanley Wheelright from releasing a toxin that causes nightmares. The mission makes Team Bartowski suspicious of where Chuck's Mom's allegiances lie. Jeff and Lester make Halloween plans for the Buy More while Ellie and Awesome get a visit from Awesome's mom.

In order to avoid Sarah after their first real fight Chuck heads out on a rogue mission. Meanwhile Ellie digs into the Bartowski family history.

Chuck aims to impress by attempting a dangerous mission meanwhile Casey and Morgan try to protect Jeff and Lester from the truth when they snoop around to find out Greta's identity.

Chuck, Sarah, Casey and Morgan venture into the jungles of Southeast Asia when The Belgian attempts to unravel the secrets of the Intersect.
Meanwhile, Captain Awesome and Ellie try to decipher a secret left behind by her father.

It's the day after Thanksgiving and Chuck faces the most awkward of family reunions when mom comes over for dinner - along with the dangerous Alexei Volkoff. Back at the Buy More, Morgan deals with the busiest shopping day of the year as Jeff and Lester hatch their latest scheme.

When an assignment brings him to a French vineyard, Chuck juggles tracking down a nano-chip with trying to create the perfect romantic getaway for Sarah. Back at the Buy More, Lester comes to Big Mike for his own romantic problems.

Sarah takes dangerous measures to help Mary Bartowski bring down Alexei Volkoff, as Chuck worries that she may be getting in too deep. Sarah, though, must enlist the help of Chuck, Morgan and Casey to complete her undercover mission. Meanwhile, Ellie and Awesome are at odds over what to name the baby.

As Sarah works to free Chuck's mom, Chuck and Morgan embark on their own mission to take down Alexei Volkoff. Meanwhile, Casey bonds with his daughter, Alex, while Ellie tries to ease Awesome's anxieties over fatherhood.

Casey, Chuck and Sarah are sent to Morocco to rescue Roan Montgomery. Meanwhile Morgan plans to meet Alex's mother and Mary spends some time with her family.

Chuck surprises Sarah with her old spy team, The C.A.T. Squad, leading to a mission in Rio. As The C.A.T. Squad works to settle a score with Augusto Gaez, old secrets and grudges come to light. Back at the Buy More, Morgan fends off the advances of Carina, a former flame and frisky member of The C.A.T Squad.

Valentine's Day is interrupted when Chuck and the team are sent on a mission to England to protect a reclusive young heiress, Vivian McArthur. Meanwhile, Casey gets an offer from the mysterious Jane Bentley. Back at home, Ellie and Awesome find an unlikely solution to a parenting problem, as Morgan ponders a big move.

Chuck encourages Vivian to get in touch with her inner villain for a mission; Morgan's search for a new roommate has unexpected results.

Chuck and Sarah suspect Casey is carrying out private missions; Chuck fears the CIA's new operatives will render him obsolete; Morgan settles in with a new roommate; Awesome becomes uncomfortable with Ellie's research.

Chuck is put in charge of a top-priority mission, but his leadership skills are pushed to the limit when there is a cuddle in Castle. Meanwhile, Awesome takes on a mission of his own when Ellie finds an alarming new hobby. Elsewhere, Morgan's leadership is also tested when his Buy More troops wage war against Large Mart.

Sarah throws Chuck a surprising relationship curveball as the CIA orders Vivian Volkoff assassinated. In order to prove Vivian's innocence, Chuck must put his trust in a dangerous ally - her father Alexei Volkoff. Meanwhile, Ellie suspects that her mother is interfering with the search into her father's past.

When Chuck and Sarah get conned out of their wedding money, there is only one man they can turn to for help - Sarah's conman father, Jack Burton. Meanwhile, Morgan pressures Casey to face Alex's mother.

Chuck and Sarah put aside spy work to have a weekend of debauchery, but Devon's plans for Chuck's big night don't go quite as expected. Meanwhile, Ellie's investigation into her father's computer leads to a life-changing discovery.

Chuck and Sarah's wedding planning includes one final detail: ensuring that the mother-of-the-groom makes it to the ceremony on time and alive. Meanwhile, Morgan's responsibilities as Best Man include his most dangerous mission yet, as he faces Vivian Volkoff.

Before he can kiss the bride, Chuck must enlist his wedding party to take down Vivian Volkoff and stop her from destroying the big day. When he turns to Alexei Volkoff for help, the CIA sends its toughest agent, Clyde Decker, to stop them.