When Casey's former commanding officer returns, Chuck and Sarah take it upon themselves to clear his name when he is arrested for treason.

As the episode begins, Marine 2nd Lt. Alex Coburn is being reviewed by a ranking officer regarding his application to special forces training while in Honduras in 1989.

Later at Castle, Beckman issues the team their orders to test the security at a secret government holding facility.

Back at Castle, Beckman congratulates the team on their success, but reveals the test came too late: Someone has already broken into the vault and stolen a prototype drug called Laudanol, an emotional suppressant designed for agents to control their feelings in the field.

As Sarah reaches for her gun, and Beckman confronts Casey, he chooses to plead the 5th to avoid incriminating himself and is arrested.

When cornered by a team led by the security specialist, Chuck and Sarah play to his ego and convince him they are there to review the changes.

He then leads them safely to the lower levels where, after another alert is triggered, Sarah knocks him out and steals the keycard needed to access the prisoner holding cells but they are too late.

Coburn was officially killed in action in Honduras on the same day John Casey appeared as a new recruit on Keller's black ops team.

He admits to the team that Keller is blackmailing him into recovering the Laudanol and Casey left behind a fiancee named Kathleen McHugh (Alexandra Bromstad in flashbacks/Clare Carey present day) when he faked his death.

Casey is astonished when he realizes that Alex McHugh (Mekenna Melvin) is his daughter, but stands by his decision not to involve himself in their lives.

Devon is less than thrilled, as he sees getting out of the country as a way to protect Ellie from any danger brought on by Chuck's spy life.

When she arrives home to tell him, she instead finds him throwing a private celebration for her, and he admits that it is Ellie's happiness that matters, and agrees to support her.

While TVFanatic.com noted the 15-level assault mission as "video game-esque" and "definitely pushing just how cheesy we can forgive the show for being," they lauded the action scenes, comedy, and character development.

[4] Alan Sepinwall found an episode forcing the typically stoic Casey to face a painful moment from his past as a great showcase for both the character and actor Adam Baldwin, and further praising the action scenes as well as the return to the dynamic between the three main characters largely missing from the third season.