As the longest-running series in the Arrowverse, Arrow has seen more than its fair share of antagonists with their own designs for Star City and plans to stop Oliver Queen. However, the character that eventually took down Green Arrow for operating outside of the law and exposed Oliver Queen's vigilante double life wasn't a villain at all. Instead, she was FBI agent Samanda Watson, portrayed by Sydelle Noel (GLOW).

With the final season of Arrow starting soon, we're taking a look back at the character who took on Oliver Queen and criminal mastermind Ricardo Diaz all over the course of Arrow's sixth season.

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WHO IS SAMANDA WATSON?

Arrow Samanda Felicity

After a photo of Oliver Queen dressed as Green Arrow goes public, Watson arrives in Star City in Season 6's second episode to launch a full investigation on Oliver while he serves as the city's mayor. Convinced Oliver was the Green Arrow, Watson dogged him relentlessly for the killings he had committed while operating outside of the law as the superhero. As part of her investigation, Watson interrogated each of the members of Team Arrow, except Mister Terrific who remained elusive thanks to his technology. Ultimately, Wild Dog implicated Oliver as the Green Arrow after Watson threatened to keep Rene Ramirez's daughter from him if he refused to testify.

Having secured Rene's testimony, a confident Watson arrests Oliver over Thanksgiving in front of his son William. Before being taken into custody, Oliver vows to sue Watson personally upon his acquittal for wrongful prosecution. Ultimately, the court finds Oliver innocent and drops the charges against him while Watson returns to Washington, D.C. after being reassigned.

The Surrender of Oliver Queen

After the criminal mastermind Cayden James is usurped by Ricardo Diaz, that villain outwits Team Arrow at every possible turn in his bid to take over Star City, Oliver turns to Watson for help out of desperation. Without any options, Oliver agrees to confess to being the Green Arrow in exchange for the FBI's help in bringing Diaz down to which Watson agrees. Watson would work with Team Arrow in coordinating FBI raids on Diaz's assets and allies, including police precincts he had paid off for evidence against the crime lord.

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While Diaz initially evaded capture, Oliver held a press conference announcing himself to the world as the Green Arrow and willingly going into custody. For the years spent operating as a vigilante, including killing many criminals without legal jurisdiction for the first several years of his illicit career, Oliver was convicted and sent to a maximum security prison to carry out his sentence while the FBI continued to hunt for Diaz on the outside.

Samanda Watson in Season 7

Five months after Oliver's incarceration, Diaz remained on the loose leading a frustrated Felicity Smoak to confront Watson over keeping up her end of the bargain. Watson is nonplussed until she learned of a new group of figures active in Star City calling themselves the Longbow Hunters leading her to attempt to relaunch the case against Diaz until she is stopped by her superiors, who believed the crime lord to no longer be a threat.

Using her connections to discover Diaz is targeting the Centers for Disease Control and still stonewalled by her boss, Watson reluctantly agrees to work with Team Arrow to stop him, but the group fails, which leaves Watson remanded to a permanent desk job in Washington for operating outside of her clearance and in direct insubordination of her superiors. Although Oliver was ultimately freed from incarceration, this brought an end to Team Arrow's association with Watson for the foreseeable future.

Returning Tuesday, Oct. 15 at 9 p.m. ET/PT on The CW, Arrow stars Stephen Amell as Oliver Queen, David Ramsey as John Diggle, Rick Gonzalez as Wild Dog, Juliana Harkavy as Black Canary, Katie Cassidy as Black Siren, Katherine McNamara as Mia Smoak, Joseph David-Jones as Connor Hawke and Ben Lewis as William Clayton-Queen.

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