This is a crucial time for "Constantine" fans. Ever since Matt Ryan reprised his role as John Constantine in an "Arrow" episode, people have become interested in the character again. If fans play their cards right, the network just might hear them and the short-lived series might have a season 2. If they're really lucky, the long awaited movie sequel might even happen. 

NBC cancelled the supernatural TV series after only one season due to its less than stellar ratings. "Constantine" actually has a strong fan base and its numbers weren't bad, especially in delayed viewership, but it was enough for the network. 

Ryan's one-off appearance in episode 5 of "Arrow" season 4 has caught people's attention. In the episode titled "Haunted," Constantine arrived to help restore Sara's soul after she was resurrected in the Lazarus Pit. A flashback in the episode also revealed how Oliver and John met and became friends. "Haunted" gave the show its highest ratings since "Arrow's" season 4 premiere, undoubtedly bolstered by "Constantine" fans who tuned in just to see their favorite demon hunter. 

It's not just the fans who enjoyed Ryan's appearance in "Arrow," though. Showrunner Marc Guggenheim had long expressed a desire to integrate the character in the series' universe. 

The success of the Constantine-centric "Arrow" episode has bolstered fans hopes about their favorite show returning. Some have even started a change.org petition to Save Constantine and bring the show back to the small screen. The petition referenced the "Arrow" episode and encouraged networks to pick up the show for another season and guaranteed that "Constantine" fans will bring in the ratings and the revenue. So far, the petition has garnered 50,000 signatures. 

Hopefully one of those networks would take a chance and develop another season of "Constantine." A sequel to the Keanu Reeves movie of the same name would also be very welcome. In an interview he gave to RTE TEN earlier this year, the "John Wick" star revealed that he wishes he can do a sequel to "Constantine" as he had always wanted to play the character again.