Dean (Jensen Ackles) pressures Sam (Jared Padalecki) into visiting Cicero, Indiana, so he can visit an old flame named Lisa (guest star Cindy Sampson), he had a tryst nine years ago. However, Dean is stunned when he meets not only Lisa again, but also her 8-year old son Ben (guest star Nicholas Elias), who bears a striking resemblance to him.
However, Ben soon goes missing and Sam and Dean discover that a Changeling, a demonic parasite, is snatching kids from the small town and assuming their form. Meanwhile, Ruby (Katie Cassidy) makes contact with Sam and reveals some startling information about his mom.
Phil Sgriccia directed the episode written by Sera Gamble.