Sara's resurrection went slightly awry after Laurel and Thea lowered her body into Lazarus Pit, and it will take Oliver's old friend Constantine to reunite her body and soul with a little black magic.

Matt Ryan will reprise his lead role as the demon hunter and master of the occult, John Constantine, from the short-lived NBC series, "Constantine," cancelled earlier this year. Oliver Queen (Stephen Amell) calls his mystical pal when Sara takes an ever greater turn for the worse.

"We weave in the Constantine character very nicely," Amell told TVLine. "Keeping within the framework of our show, we lend ourselves to the things that make Constantine fun as a character "

Amell also had expressed earlier interest in crossing over on "Constantine" had the show received a second season. The DC Comics characters' shows are under the Warner Bros. Television studios.

Constantine will debut in the "Arrow" episode "Haunted" on Wednesday, Nov. 4 at 8 p.m. on The CW.