"Supernatural" is coming back this March 18 with episode 15, "The Things They Carried." It will bring the season closer to its finale and it will also mark the show's new running schedule — it will now air on Wednesday night instead of Tuesday. 

This new schedule was made to give air time to the new CW show, "iZombie," which will now take the Tuesday slot. "Supernatural" will now air right after another popular CW series, "Arrow".

The official synopsis of episode 15 reads as follows: 

"Despite Dean's (Jensen Ackles) directive to forget about looking for a cure for the Mark of Cain, Sam (Jared Padalecki) continues to do research. Dean suspects Sam is hiding something but decides to focus on a new murder case where they run into Cole (guest star Travis Aaron Wade). The three team up and learn a Khan worm is infecting men and turning them into murderers. Unfortunately, the worm makes its way into Cole." 

Dean is already in a lot of trouble after murdering Cain, and now the curse is quickly making him lose control. Getting distracted by Cole while in the midst of an investigation could spell out even more issues for him. 

This preview gives a lot of insight on what fans should expect from the upcoming episode. In episode 14, "The Executioner's Song," it was mentioned that there is no cure for the Mark of Cain and there's the possibility of Dean trying to kill Sam in order to fulfill the Mark of Cain prophecy. 

Curing Dean, or at least discovering how to help him, may be the driving force for this season's finale. Episode 15 — or to a climactic extent, episode 16 — might also introduce Rowena or Crowley as the primary antagonists of the show now that Cain is dead and out of the picture.