He played Tom Cruise's character's son and was the "next big thing" or whatever.
He's now on Lost as a guest star:
He'll be in the ep titled "Further Instructions," airing on October 11 or 18, depending on who you ask (I don't know why TPTB are switching episodes). He'll play Eddie, a sweet but torn male in his 20s. There's also a rumor that he is actually Locke's son, Rupert Locke, but I never trust Lost rumors these days.
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Better-looking now, y/n?