Yesterday, it was revealed that Matt Ryan would be showing up on Arrow as John Constantine, a role that he played in the cancelled NBC show. Now, reports are coming out of how he will be involved in his one-shot appearance during the fourth season of the CW series, reported by TV Insider.
"Unlike Thea, who wasn’t fully dead, the consequences of using the pit on someone as dead as Sara was creates some unforeseen difficulties...and John Constantine is uniquely suited to help our team deal with those."
Guggenheim continued and made it pretty clear this is a one-time deal. No news yet on what episode Constantine will appear. We'll keep you updated as more develops.