Andy was from Season 1 and a boyfriend of Prue's. He was a cop and Darryl's partner. He finds out that their witches towards the end of the season, and then some guy sends a warlock to kill the sisters. He fails, but then the guy turns back time, allowing the warlock to get more chances, then the sisters start to sense the time turning back each time. Andy gets killed by the warlock and they stop the warlock, but Prue wants time to start over so Andy will be alive again, but Andy, as a spirit, tells her to let him pass on, so she does. They then use their magic and stop time from resetting. There may be a few small mistakes in what I said since it's been like a month or two since I saw the episode.
__________________ "The MTV Movie Awards are a systemic anomaly inherent to the programming of the Matrix. Although the transport process has altered your consciousness, you irrevocably remain human. Ergo, concordantly, vis-a-vis... You know what? I have no idea what the hell I'm saying. I just thought it would make me sound cool."
-The Architect AKA Larry