'Legends of Tomorrow': Behind-the-Scenes Pic Gives First Look at John Constantine

(Photo: Warner Bros. TV/The CW)

The image, which appears on a screen in an editing room, serves as the first look at Ryan in what is likely footage from the first of his two upcoming episodes of Legends.

Ryan played Constantine on NBC's Constantine for one season, and made a guest appearance on an episode of Arrow after the show was cancelled. A CW Seed animated series featuring the character is planned for the near future.

In his Arrow appearance, Constantine made reference to a backstory he shared with Damien Darhk. That villain, who is recurring on this season of Legends of Tomorrow, will almost certainly be at the center of the episode currently in production, titled "Daddy Darhkest."

Pairing Constantine, a hard-edged cynic, with the cheerful Ray Palmer seems rife with comic potential. Fans also wonder what kind of relationship Constantine might have with Sara Lance, the captain of the Waverider, whose soul Constantine helped to reconnect with her body after her death and resurrection in Arrow.

While "Haunted," the Arrow episode on which Constantine appeared, remains one of the highest-rated ever in ComicBook.com's TV database, the episode drew some criticism at the time from hardcore Arrow fans for distracting from Arrow's season-long storyline to set up Legends of Tomorrow.

Darhk has not yet shown up on Legends of Tomorrow this season. When fans last saw him at the end of last season, he was being returned to his proper place in the 1980s and his memories of being a member of the Legion of Doom were removed so that he could fulfill his destiny of dying in his battle with the Green Arrow in 2016. Recently, actor Neal McDonough posted a photo of himself dressed in period clothing to social media, prompting fans to assume he was going to appear in the past in an upcoming episode of Legends.

DC's Legends of Tomorrow airs on Tuesday nights at 9 p.m. ET/PT, following new episodes of The Flash on The CW.