when do they find out cole is balthazar
Cole Turner In "Power Outage", Cole's superiors, the demonic Triad, learn that he may have developed genuine romantic feelings for Phoebe; Cole responds by killing them, forcing him into hiding. Meanwhile, the sisters acquire a target in the red-and-black-skinned demon Belthazor (Michael Bailey Smith). In "Sleuthing with the Enemy", the Charmed Ones discovers Cole and Belthazor are one and the same, but when Cole convinces Phoebe that he, being half human, truly loves her, she fakes his death so that her sisters Piper (Holly Marie Combs) and Prue will not hunt for him.