When you watch Supernatural Season 13 Episode 21, you'll see how far one family will go to reunite. Sam, Dean and Castiel are determined to find their way to the other side. They get Gabriel's grace, but it's unfortunately too weak to keep the portal opened longer than a couple seconds. Castiel comes up with the idea to capture Lucifer so they can drain his grace. Gabriel and Rowena are able to track him down, and take him prisoner, but he questions why they didn't end up killing him. Sam reveals to him they need to keep the portal opened longer than the 24 hours so they are going to keep him around to drain his grace so they can stay in the other world even longer. The group, except for Rowena, head into the other world, but Lucifer takes it upon himself to annoy her. Rowena finally has enough of him, and quickly reveals the reason the guys are on the other side is because they are not only saving Mary, but also saving Jack who will never view Lucifer as his true father. Lucifer gets angry, and breaks free of Rowena's spell, but when he tries to kill Rowena she blasts him through the portal. Want to see what happens next? Go watch Supernatural online now to see the exciting conclusion.