As Coop realizes that he has fallen in love with Phoebe, she throws him for a loop when she wants to peruse love with a mortal instead of with a magical being. Meanwhile, as Piper tracks down the demons who killed Billie and Christy's parents, she begins to suspect that the demons and the sisters are somehow connected to the Ultimate Power. Paige turns to Coop for help with some issues she has in regards to her marriage to Henry. Christy tries to convince Billie that the Charmed Ones are out to get her.
Spoilers ahead. Coverage follows the scope labeled below.
Complete story — includes the ending
Coop comes to the conclusion that he has fallen for Phoebe. Piper is on the hunt for the remaining Noxon demon in order to interrogate him about who he's working for, but Christy just wants to kill him as soon as possible. Paige finds it hard balancing life as a Charmed One with that of a married woman. When both the Halliwells and the Jenkinses find the Noxon demon, Billie and Christy combine their powers to vanquish an unvanquishable demon making Piper realize that Billie and Christy may be the ultimate power whom they must face in the coming battle.