Charmed and Dangerous - S4-E13
Other mistake: In this episode, the Source talks about the "Ultimate Power" being the Hollow. But in Season 8, we learn that the "Ultimate Power" is Billy and Christy. (And they end up taking in the Hollow, so now are they the "Ultime Power" times 2?) Which is it? It can't be both. (00:02:05)
Chosen answer: Her agent/manager negotiated a special billing as part of her contract. It distinguishes her from the rest of the cast, probably when she became a producer on the show.
JC Fernandez