Devil's Trap

On a mission to save their father from Meg, Sam and Dean seek help from an old family friend, Bobby. When Meg shows up on Bobby's doorstep, the brothers lure her into a trap and exorcise the demon from her body after learning where John is being held prisoner. While trying to rescue John, the demon shows up and a full battle ensues between the Winchesters and the demon they have been searching for all their lives.