SPOILER WARNING: This article contains major spoilers for "Haunted," the latest episode of "Arrow," which has not yet aired on the west coast as of publication.
Matt Ryan made his much-publicized return to the role of John Constantine on tonight's "Arrow," titled "Haunted." While the character isn't seen in the present day until the third act, the episode contained something of a surprise: John Constantine and Oliver Queen (Stephen Amell) actually go back a ways, with Ryan also showing up in the episode's flashback sequences.
Turn out, the two originally met years back on Lian Yu -- the "hellish island" that Oliver has returned to in the season four flashbacks -- when Constantine went looking for a mystical object, as he is wont to do. On the island, Oliver ends up saving Constantine's life, leaving Constantine owing Oliver a favor -- one he calls in, leading to their present-day encounter.
Matt Ryan Reveals Secrets Behind Constantine's "Arrow" Resurrection
In the main timeline, Constantine is enlisted, as had been previously revealed, in helping restore Sara's (Caity Lotz) soul following her resurrection via Lazarus Pit. The "restitution" trip to the "other realm" is successful, and the episode ends with the door open for Constantine to potentially return to the show in the future -- though he does warn Oliver that mystically-powered season four villain Damien Darhk (Neal McDonough) is someone to be taken very seriously. (Constantine's advice: "You watch yourself around that one, mate.")
Ryan starred in the DC Comics-based "Constantine" for 13 episodes on NBC, running from October 2014 to February 2015. Though the show was canceled after its initial run, it was announced this past summer that Ryan would reprise the role in a guest-starring appearance on "Arrow," which airs 8 p.m. Wednesdays on The CW.