Constantine may have been cancelled, but fans of the show will get to see the character back on air as part of a crossover episode, in Arrow season 4. The recently released synopsis for episode 5 hints at John Constantine's connection with the world of Arrow.

The official synopsis reveals that Oliver Queen and Constantine are "old friends". It will be quite interesting to see a backstory on this and flashback scenes in the episode could delve into the history behind Oliver and Constantine's friendship. Check out the full synopsis below:

A demon hunter and dabbling master of the occult, Constantine might just fit well into the fourth season of Arrow which Stephen Amell earlier described as "full of magic and mysticism." The DC Comic character had his own show on NBC which got cancelled post its season 1 run due to low ratings. Since then, fans of the antihero have been rooting for the show to be back on air.

"When things take a turn for the worse with Sara (guest star Caity Lotz), Oliver (Stephen Amell) calls in a favour from an old friend who deals in the mystical, John Constantine (guest star Matt Ryan)."

The character will reportedly help bring Sara Lance back from the dead. Whether this appearance from Matt Ryan's John Constantine is really going to be a one-off or the start of something bigger remains to be seen, but it will be great to see the DC superhero again.

"When you see him in the show, honestly it feels like we're doing a Constantine/Arrow crossover, and it's so exciting," Arrow executive producer Marc Guggenheim told Superhero Hype in an earlier interview.

"We're just really glad we got the chance to extend Matt Ryan's run as Constantine by at least one more hour of television. I think you'll see he fits very neatly into our universe. It never feels forced, it feels right."

Arrow season 4 airs on Wednesdays at 8pm ET/PT on The CW.