Oliver Queen and Team Arrow have faced plenty of deviously scheming villains in Star City over the course of the DC TV series. However, none of them have been as calculating as Cayden James. Leading an organization of hackers known as Helix, James personally holds Oliver for the death of his son and created the clandestine group to achieve his revenge.

Now, CBR is taking a look back at Arrow's Cayden James, his master plan and how he was ultimately defeated by a surprising character.

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WHO IS CAYDEN JAMES?

Cayden James and Anatoly on Arrow

While secretly leading the hacktivist collective Helix and targeting people that actively exploit anyone weaker and poorer than them, James' obsessive commitment to Helix's mission eventually leads to a divorce with his wife and his estrangement from his son Owen. After hacking a major pharmaceutical company, James is arrested by A.R.G.U.S. while watching one of Owen's high school basketball games in an effort to reconcile with him.

Before being transferred to an A.R.G.U.S. facility, James learns that Owen was murdered, leaving the cyber-criminal heartbroken and swearing revenge on whoever was responsible. After being freed by the remnants of Helix and its former member Felicity Smoak to help Team Arrow against Prometheus, James refuses to help his former protege as he sets out to discover who killed Owen. After learning Green Arrow had killed Owen while Oliver was still regularly employing lethal force, James deduces that Oliver is the vigilante and sets out to destroy him.

The Revenge of Cayden James

After seeing a video of the Black Canary's evil double from another world, Black Siren, in action. James recruits her in his mission for revenge. Targeting a government facility as part of his goal to destroy the internet and plunge the world into chaos, James reveals that his true goal was only to lure Felicity into stopping him. In doing so, she would leave her digital signature in a restricted firewall, and he could thus thus frame her for his attack as revenge for working with Oliver and betraying Helix.

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Turning their attention directly to Star City, James and Black Siren ally themselves with Ricardo Diaz, Vincent Sobel and Anatoly Knyazev in their shadow organization. After launching a wave of terrorist attacks against the city while turning public favor against vigilantes like Green Arrow, James issues a blackmail to Oliver, then mayor of Star City a ransom of $10 million a day to stop the attacks. While exposing James' activities to the public, Oliver is eventually forced to begin paying off James with the city budget to keep the people safe.

WHAT HAPPENED TO CAYDEN JAMES ON ARROW?

Michael Emerson as Arrow's Cayden James

Team Arrow and the Flash discover security footage of Owen's death and discover that the footage was doctored to frame Green Arrow for the murder. Sharing their findings with James, the shocked criminal mastermind allows himself to be subdued by Oliver and taken into custody. Helping Team Arrow track down the remaining members of his organization, James pledges to return the city's money and begs Oliver be a better father than he ever was.

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Left alone in a police interrogation room, James is confronted with a surprise visit from Diaz who reveals that he has used a portion of James' funds to bribe the Star City police. Diaz brutally strangles James to death, has the police cover-up the murder, taking over the remnants of James' criminal organization. Now faced with an even greater threat, Team Arrow is forced to make significant sacrifices to take down Diaz and shut down Cayden James' legacy for good.

Cayden James brought together several villains to give Team Arrow its own rival organization to fight for the fate of Star City from the shadows. Blaming Oliver Queen for his losses and aware of his identity as Green Arrow, James was a particularly formidable antagonist who inadvertently fueled Season 6's true threat: the tactically brilliant Ricardo Diaz, a villain who would force Oliver to compromise his own well-being like never before.

Airing Mondays at 9 p.m. ET/PT on The CW, Arrow stars Stephen Amell as Oliver Queen, David Ramsey as John Diggle, Emily Bett Rickards as Felicity Smoak, Rick Gonzalez as Wild Dog, Juliana Harkavy as Black Canary, Colton Haynes as Arsenal, Kirk Acevedo as Diaz and Katie Cassidy as Black Siren.