When your show's star embarks on an arena tour mid-meltdown in an attempt to explain himself, it's probably time to move on. After the ghoulishness of the Charlie Sheen spectacle calmed down, showrunner Chuck Lorre still had to deliver a product, so he brought in Ashton Kutcher as Walden Schmidt, an internet billionaire who became Jon Cryer's foil for the show's final four seasons. Ratings dropped off after the novelty wore off, and an I Now Pronounce You Chuck and Larry-esque plot was hatched in which the two men of the house pretended to be gay for the sake of an impending adoption. Even the half-man would eventually depart, following an aggressive conversion to Christianity, and Amber Tamblyn filled his place, which was undeniably an upgrade.
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