The CW’s ‘Flash’ Adds ‘Royal Pains’ Alum as Genius Physicist

The CW's Flash pilot is adding a genius physicist.

Tom Cavanagh has joined the cast of the Arrow spinoff, The Hollywood Reporter has learned.

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Glee alum Grant Gustin stars as Barry Allen/The Flash in the pilot, which serves as an origin story similar in vein to Arrow. Barry, introduced in Arrow's two-part winter finale in December, is a Central City assistant police forensic investigator who arrives in Starling City to look into a series of unexplained robberies that may have a connection to a tragedy in his past.

Cavanagh has been cast in the main role of Harrison Wells, described as a rock star in the world of physics. The mind and money behind Central City's S.T.A.R. Labs Particle Accelerator, he becomes a pariah after the lab's explosion, but charts his path to redemption when he discovers that his failed experiment had the unintended consequence of creating the world's fastest man.

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The news comes as the Flash pilot nears the end of its casting process. Cavanagh joins a cast that already includes Jesse L. Martin as Detective West; Candice Patton as West's daughter and Barry's love interest Iris; Danielle Panabaker as Caitlin Snow, a bioengineering expert; and Rick Cosnett as Detective Eddie Thawne. This leaves one main role open: Hartley Rathaway.

Arrow's Greg Berlanti, Andrew Kreisberg and director David Nutter will serve as executive producers on Warner Bros. TV's eyed spinoff. Berlanti, Kreisberg and DC Entertainment's Geoff Johns will write the pilot script, with Nutter directing. Melissa Kellner Berman will serve as co-executive producer.

Flash was originally slated for a backdoor pilot on Arrow airing in the second half of the season, similar to how The Vampire Diaries helped launch spinoff The Originals last year. The change in tune is an effort for Flash to debut "with a bang like we launched Arrow," CW president Mark Pedowitz told reporters in January at the TCA winter press tour.

Cavanagh's TV credits include Ed, Love Monkey and Trust Me, as well as stints on Eli Stone, Royal Pains, Scrubs, The Goldbergs and Blue Bloods. He is repped by UTA and Circle of Confusion.

Email: Philiana.Ng@THR.com
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Philiana Ng