Impeachment hearings may be the least of Mayor Queen's troubles, as in next week's episode of "Arrow" he's also targeted by the Vigilante.

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As the promo for "Fighting Fire with Fire" shows, the Vigilante declares himself Mayor Queen's judge, jury and executioner. When the Vigilante kidnaps Oliver, Team Arrow will have to rescue him, as Oliver is left without his bow and costume.

The Vigilante debuted in the seventh episode of the season, but his true identity has yet to be revealed. The character is inspired by the DC Comics character of the same name, whose alter ego was Manhattan District Attorney Adrian Chase. If "Arrow's" Vigilante turns out to be Adrian Chase, the Star City D.A. played by Josh Segarra, it would make sense that he leaked details of Oliver's involvement in the cover-up of Detective Malone's death, triggering impeachment proceedings.

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VIGILANTE ATTACKS MAYOR QUEEN – Oliver (Stephen Amell) faces his biggest challenge yet as mayor. Felicity (Emily Bett Rickards) continues down her dark path with Helix. After Vigilante attacks Oliver while he’s acting as the mayor, Diggle (David Ramsey) leads the team in a mission to stop Vigilante once and for all. Michael Schultz directed the episode written by Speed Weed & Ben Sokolowski. Original airdate 3/1/2017.

Airing Wednesdays at 8 p.m. ET/PT on The CW, “Arrow” stars Stephen Amell, Emily Bett Rickards, David Ramsey, Willa Holland, Paul Blackthorne and Echo Callum.