When Cole re-emerges, causing a rift between Phoebe and her sisters, he attempts to re-ingratiate himself with his demonic peers, the Brotherhood of the Thorn, as the sisters' double agent. When Prue and Piper are both killed following a successful mission by the Source's assassin Shax (Michael Bailey Smith) in the season finale "All Hell Breaks Loose", Cole begs the Source (again, Michael Bailey Smith) to turn back time and prevent the exposure of magic. The Source agrees on the condition that Phoebe remain in the Underworld under his command, though he secretly orders her to be killed. Shax attacks the Halliwell Manor once more after time is reversed, but this time Leo (Brian Krause), Piper's husband who is also the sisters' guardian angel (whitelighter) is not available to heal either Piper or Prue, who lie gravely wounded.