Mr. Chow is also a kind of helper guy (the kind of I've personally played) in In the Mood for Love, doing maintenance, lending a shoulder to cry on, etc. As in Vertigo, though, the heartbreak that ensues shakes up the helper guy's soul. A few years later, in 2046, Mr. Chow has become the antithesis of the helper guy; he is instead the commitment-phobic charming rogue. A psychologically dubious transformation or an incisive portrait of helper guy mutation?
There's Newland Archer, the constant consort and companion to the socially ostracized Countess Olenska in The Age of Innocence, forever at her side, wanting to jump her bones but couldn't make the move in the end.
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And how about Casablanca? In romantic triangle situations, I would fancy myself as a jaded Rick Blaine, but isn't he finally the self-sacrificing helper guy, hanging around and trying to steal the wife before giving up and helping the couple get away? On second thought, no: since Rick spent the entire movie not being a helper guy before finally giving in, he's more a dude given to noble romantic gestures rather than being cut from the same cloth as parasitic helper guy Holly Martins.
Still, this sucks. I just found out that I spent my adult life worshipping cinematic odes to my romantic rivals. What's next? Biographers reveal the helper guy in Murakami and Lou Reed? Abe Lincoln, great statesman and helper guy?