Team Arrow will face off with a new villain named "The Calculator" after he blackmails Roy Harper (Colton Haynes) and tries to destroy Star City in Wednesday night's all-new episode of "Arrow."

A sneak peek of the upcoming installment, which is titled "Unchained," teases the unfortunate circumstances that will reunite Roy with Team Arrow. In the clip, Roy wakes up on a table surrounded by the team after being shot by Oliver (Stephen Amell). When questioned about his return to Star City, Roy explains that he received an email from a mysterious villain named The Calculator who threatened to expose his true identify if he did not steal for him.

During an interview with TVLine, executive producer Wendy Mericle opened up about Roy's return and how it ties into the storyline about The Calculator, played by guest star Tom Amandes . According to the Mericle, Amandes will make his first appearance as Noah Kuttler, a criminal mastermind and technical genius who uses his advanced skills in computer scions and Internet manipulation to blackmail Roy to do his bidding. 

"Roy comes back in a really surprising, new way. Like Oliver, he seems to have fallen back into some old habits," Mericle said.

In addition, the EP revealed that Amandes' character will "have a connection to Felicity," reports EW.

A synopsis for "Unchained" also reveals that Katrina Law will return as Nyssa al Ghul.

"The team faces off against a formidable villain nicknamed The Calculator (guest star Tom Amandes). Meanwhile, Nyssa (guest star Katrina Law) makes her move and Roy Harper (guest star Colton Haynes) returns to Star City," states the synopsis, according to CarterMatt.

Another video teases Nyssa's escape from confinement after members of the League of Assassins help her break free. She will then take on Malcolm Merlyn, the man who succeeded her father as the new Ra's al Ghul.

Season 4, Episode 12 of "Arrow," titled "Unchained," will air on Wednesday, Feb. 3 at 8 p.m. ET on The CW.

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