A popular U.S. senator and presidential candidate succumbs to illness at a fundraiser and Vogler assigns House to his case. He also tells House he can keep his whole team if he endorses Vogler's pharmaceutical company. The Senator's initial diagnosis seems to point to AIDS, but House digs deeper for another answer. Meanwhile, he also handles a case of a woman who apparently gets pregnant without having sex. Cameron visits House and tells him that she's leaving her job.