The CW has released promotional stills for Arrow season 4, episode 5, “Haunted,” featuring John Constantine from the canceled NBC series.

We reported earlier this summer that Constantine would be making a guest appearance on Arrow this fall and that his appearance would tie into Sara Lance’s resurrection. Now that Sara has returned from the dead but is being affected by the Lazarus Pit, it is time to call in reinforcements.

The synopsis for “Haunted” reads: “When things take a turn for the worse with Sara (guest star Caity Lotz), Oliver (Stephen Amell) calls in a favor from an old friend who deals in the mystical, John Constantine (guest star Matt Ryan).”

See the promotional stills from the episode below:

If we had to guess, we’d speculate that Sara attacks Thea (based on her being in the hospital), which pushes Oliver to call in Constantine to help retrieve Sara’s soul (which Damien Darhk told Lance was missing in “Beyond Redemption”).

Malcolm told Thea in “Restoration” that the only way for her to be rid of the Lazarus Pit-induced bloodlust was to kill the one who hurt her; while Thea can’t do that with Ra’s, Thea is technically the one who killed Sara. The grey areas in that dynamic likely wouldn’t matter to Sara in her current condition.

When the crossover was first announced, EP Marc Guggenheim said, “We are thrilled to have Matt Ryan reprise the role of John Constantine on an upcoming episode of Arrow. Matt is an incredibly talented actor and his portrayal of this beloved character was always something we admired.”

He added, “The introduction of magic and mysticism on the show this season has provided a truly organic opportunity for us to bring John Constantine to Arrow and the CW’s DC universe. It will be a well-deserved tip of the hat to all the Constantine fans who were so incredibly supportive of that series.”

As for whether Constantine might appear on future episodes of Arrow, EP Wendy Mericle said, “Right now, it really was — it’s born out of necessity for this particular story,” adding, “[I]t is a one off, and this is what we’re focusing on right now.”

Arrow airs Wednesdays at 8:00 p.m. ET on The CW.

Are you looking forward to Constantine on ‘Arrow’?