Chuck is overcome with jealousy when his nemesis -- & Sarah's ex-lover & former partner -- Bryce Larkin (recurring guest star MATTHEW BOMER) makes an unexpected return. Chuck & Sarah's growing feelings for each other are tested when their latest mission requires Sarah & Bryce to pose as an extremely affectionate couple. Meanwhile, Morgan faces his own challenge at Buy More when he must deal with a gang of bullies from a neighboring sporting goods store in the strip mall called the Mighty Jocks, led by the fearful & intimidating bully, Mitt (guest star MICHAEL STRAHAN
- New York Giants).
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Chuck learns more about Sarah's past when they run into her old high school nemesis, Heather Chandler (guest star NICOLE RICHIE
-
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The espionage life is beginning to take its toll on Chuck & everyone is noticing. Chuck tries to explain his unusual behavior to Ellie & to the quirky Buy More efficiency expert Emmett Milbarge (guest star TONY HALE
- " Arrested Development, Stranger than Fiction"), but a new assignment only complicates things. After a global terrorist comes searching for Jeff, Chuck is forced to socialize with Jeff in order to find out what role the oddball plays in the mission. Sarah, Casey & Chuck are all shocked when they discover that the fate of the world & the prevention of World War III rest in Jeff's hands.
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While on a Nerd Herd call, Chuck runs into his ex-girlfriend Jill (recurring guest star JORDANA BREWSTER
- " The Fast & the Furious")
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Chuck & Jill (recurring guest star JORDANA BREWSTER) are enjoying the honeymoon stage of their rekindled relationship. The two lovebirds plan a weekend getaway but have to cancel at the last minute when Casey & Sarah inform Chuck that he is needed for an immediate mission to find corrupt agents in the CIA. Jealousy erupts when Jill finally meets Sarah & learns that Chuck & his handler must pose as a couple. Chuck does his best to reassure Jill that his relationship with Sarah is purely business but only finds himself in more trouble when his mission does not go as planned. Meanwhile, corporate efficiency expert Emmett (recurring guest star TONY HALE) is out to get Chuck & interrogates Morgan to get some dirt on his best friend. ...

Chuck is still reeling from the discovery that his ex-girlfriend was a Fulcrum agent & goes on a mission to take his mind of off his shock. Casey gets a shock of his own when he finds out that his sensei, Ty Bennett (guest star CARL LUMBLY
- " Alias, Buffalo Soldiers, Cagney & Lacey"), who taught him everything he knows, is now one of the most-wanted rogue agents. While on the search for Bennett, it becomes clear that Casey may be too emotionally involved to continue with the mission. Meanwhile, Captain Awesome's parents, Honey (guest star MORGAN FAIRCHILD
- " Fashion House, Friends, Falcon Crest") & Woody (guest star BRUCE BOXLEITNER
- " Babylon 5, Young Blades, Scarecrow & Mrs. King"), make a surprise visit to help Ellie & Awesome plan their wedding. Meanwhile, at the Buy More, Emmett (recurring guest star TONY HALE) reinstates the employee of the month contest, but Morgan, Jeff & Lester have other plans.


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In the third season premiere, now that Chuck has new Intersect abilities, he trains to become a full-fledged spy -- but when he flunks out of spy school & loses Sarah in the process, he hits rock bottom. Morgan returns from training to be a chef at Benihana to help Chuck get out of his funk. But will he? Or is Chuck destined to return to his old life? ...

Casey carries out a side mission for his old commanding officer, Colonel James Keller (guest star Robert Patrick
- Terminator
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Chuck learns that his latest solo mission will be a final test to see if he is ready to be a spy. Chuck needs to put everything he has learned into action to avoid going back to his old life while Sarah & Shaw (recurring guest star BRANDON ROUTH) observe his every move. ...