Now in complete control of the "Book of Shadows," Zankou (Oded Fehr) prepares to take on the "Ultimate Powers" of the Shadow -- and, in the bargain, to absorb all the powers of the Charmed Ones. Meanwhile, Homeland Security agent Keyes (Glenn Morshower) begins putting two and two together regarding the mysterious deaths and disappearances of many of the girls' previous associates. As this final episode of Charmed's seventh season races to its climax, our heroines are faced with two dilemmas: they must vanquish Zankou without revealing themselves as witches to the suspicious Keyes -- and if they don't relinquish all of their powers immediately, they will die! ~ Hal Erickson, Rovi