"Arrow" executive producer Greg Berlanti announced that Constantine will not be returning to the show. He hinted that Matt Ryan's cameo in "Arrow" was a one-time thing and the show did not have a place for his character anymore. While the announcement disappointed a lot of fans, "Legends of Tomorrow" producer Phil Klemmer said it would be a sin for him not appear in their universe.
Berlanti announced during the Television Critici's Association press tour that they have not planned anything for Ryan's character Constantine. According to Screen Crush, he explained that the character existed in a different DC universe and the studio had something separate in store for it. Constantine, as Berlanti notes, was a complicated character and it's difficult to incorporate in a single comic book series.
The special cameo of Constantine in "Arrow" Season 4 was CW"s vocal support for Ryan's character after the show was shut down by NBC. The episode gained favorable ratings from its fans who were hoping that the show would pick up his character at some point. But Berlanti's announcement was indicative that Ryan's appearance might be a one-time thing.
But fans should not be disheartened because Klemmer might have ideas for Constantine in "Legends of Tomorrow." He told Zap2it that it would be a sin not to include Ryan's character in the show. Though they won't be adding his character anytime soon, he confirmed that he has Constantine in mind for his feature plans for the show.
Meanwhile, "Constantine" Season 1 is currently available in CW Seed.