'Two And A Half Men': Patton Oswalt Plays Walden's Bitter Old Business Partner (VIDEO)

A quick call from his ex-wife Bridget rekindled some old bitterness in Walden on "Two and a Half Men" (Mon., 9 p.m. EST on CBS). Most of Walden's time on the series has been about his love life, but it was his professional life that made him a billionaire. And he did so side-by-side with his partner Billy Stanhope, played by Patton Oswalt.

When Billy showed up at his front door, Walden wanted nothing to do with him. Bill hadn't wanted to sell their initial technological development, and had gone online to tear down Walden in a series of increasingly disgusting and disturbing videos. But in the meantime, he'd managed to crack something they'd been working on before their falling out. Only he needed his old partner to help him do it. And both men were convinced it was another billion dollar idea.

So of course, Alan invited Billy in. Dollar figures like that are simply too irresistible for the perpetually poor "leech." But it was the excitement of creating again that got Walden back on board, and immediately competing again with Billy. Their competitive nature was exemplified by a pee stand-off. While working in tandem on the program, they took turns trying to convince one another to urinate, until finally they both cracked at the same time and peed off the back deck. There, Billy revealed that he was not only back to work with Walden on this project, he was also now sleeping with Bridget.

Catch "Two and a Half Men" on Mondays at 9 p.m. EST on CBS.

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