Years before Zachary Levi suited up as DC Comics' brightest new superhero Shazam, the actor was busy saving the world from terrorists, rogue spies, and evil assassins in NBC's beloved action-comedy series, Chuck. The show, which was created by Chris Fedak and Gossip Girl creator Josh Schwartz, premiered on NBC in 2007 and ran for a total of five seasons before concluding with a surprisingly heartbreaking finale.

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The series follows computer nerd and Buy More employee Chuck Bartowski, who is thrust into the world of international espionage when he opens an email encoded with dangerous government secrets that are downloaded into his brain. With spies, terrorists, and assassins looking to steal what's in Chuck's brain, he must work with CIA Agent Sara Walker and NSA Agent John Casey to protect the governments most dangerous secrets and stop some of the world's deadliest criminals. Over the course of five seasons, Chuck delivered some truly outstanding adventures, but it's fair to say they weren't all winners. Here are the five best and five worst episodes of Chuck, according to IMDb.

Worst: "Chuck Versus The Sensei" - 8.1

When Chuck, Casey and Sara are tasked with investigating the theft of a dangerous weapon, Casey is shocked to discover that his former sensei and long-time mentor is leading a rogue group of government agents. Casey is confined to Castle due to his emotional connection to the case, however, he is able to trick Chuck and escape. Meanwhile, Emmett reinstates the employee of the month competition at the Buy More and Ellie is forced to spend time with Captain Awesome's equally awesome parents.

Best: "Chuck Versus The Subway" - 9.4

While tracking Shaw, who turns out to be alive and well (with an Intersect), Chuck and the gang find themselves in what they believe to be the Ring's headquarters, but it turns out the building actually belongs to the government. With the help of Shaw, the Ring manages to take complete control of both the CIA and NSA, putting Team Bartowski in grave danger. Meanwhile, Chuck's dad returns to save his son and Ellie finally discovers the truth about Chuck's secret life.

Worst: "Chuck Versus The Helicopter" - 8

Seeing that Chuck isn't equipped to deal with the Intersect or the danger that accompanies it, the government enlists Dr. Jonah Zarnow to extract the secrets from his head. Things become incredibly difficult, however, when the doctor is seemingly assassinated by one of Chuck's new handlers, forcing him to question everything and everyone in his life. Meanwhile, Ellie attempts to learn more about Chuck's new girlfriend by inviting Sara to family dinner, which is made infinitely more intense due to the fact that Sara might be the killer.

Best: "Chuck Versus The Colonel" - 9.5

Casey holds a gun to Chuck's face

Chuck and Sara put everything on the line and turn their backs on the government in an attempt to find and rescue Chuck's father, Stephen Bartowski. Furious that Chuck and Sara have gone AWOL and left him behind, a recently promoted Casey hunts them down and attempts to bring them in. Back at the Buy More, Morgan's involvement in Big Mike's promotion turns him into enemy number one, which isn't helped when Emmett offers him the coveted assistant manager position.

Worst: "Chuck Versus The Crown Vic" - 8

Chuck and Sarah looking back

Still dealing with the fact that Sara still has feelings for his ex-best friend Bryce Larkin, Chuck "flashes" and reveals that billionaire-philanthropist Lon Kirk's yacht is being used to create, hide, and transport counterfeit bills.

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Hoping to uncover the truth and catch their guy, Chuck, Sara and Casey go undercover and find themselves in an explosive situation. Meanwhile, Morgan meets Anna's incredibly strict parents for the first time but ends up embarrassing himself and humiliating Anna.

Best: "Chuck Versus The Other Guy" - 9.5

Beckman orders Sarah and Shaw to track down the director, but Chuck begins to worry that Shaw can't be trusted when he learns that Sarah is responsible for the death of his wife.

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After being transferred to Paris, where the Ring's Cipher was built, Shaw finally reveals that he's working for the Ring and attempts to take his revenge by killing Sarah. Thankfully, Chuck and Casey arrive just in time to save Sarah, with Chuck shooting and seemingly killing Shaw in the process.

Worst: "Chuck Versus The Sizzling Shrimp" - 7.9

While in Chinatown with Morgan and Sarah, Chuck flashes on a waitress and identifies her as a dangerous Chinese agent named Mei-Ling. After learning that Mei-Ling isn't on official business and is simply trying to save her kidnapped brother, the team are ordered to not get involved. Chuck, however, is able to convince Sarah and Casey to help the Chinese agent, if she agrees to defect to the United States. On the homefront, Ellie is once again let down when Chuck misses their Mothers Day dinner and Morgan's career is put at risk by a Buy More sales competition.

Best: "Chuck Versus The Ring: Part II" - 9.5

Chuck NBC

An imprisoned General Beckman informs Team Bartowski that the Ring leaders, who are officially named The Elders, will be at a major spy convention to take over the NSA and the CIA.

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Chuck, Sarah, Casey and the gang are able to successfully capture The Elders and expose Shaw as a rogue agent, although he manages to escape. Shaw later arrives at the Buy More to challenge Chuck, with both men flashing and using the Intersect to fight one another.

Worst: "Chuck Versus The Bearded Bandit" - 7.7

Chuck and the gang take on an exciting new case for the recently formed Carmichael Industries, searching for their client's missing brother. The team quickly realizes, however, that they haven't been given the entire picture and things aren't going to be as straight forward as they seem. At the same time, Gertrude Verbanski contacts Sarah and attempts to convince her to abandon Carmichael Industries and accept a position at Verbanski Corp.

Best: "Chuck Versus The Ring" - 9.6

With the Intersect no longer in Chuck's mind, he is able to move on with his life without being threatened by terrorists, assassins and evil spies. On the day of Ellie and Captain Awesome's wedding, however, Ted Roark makes a surprise appearance and threatens to kill everyone at the wedding unless Chuck brings him the Intersect cube. Meanwhile, Sarah must finally decide if she wants to stay with Chuck or leave with her ex-boyfriend, Bryce Larkin.

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