Next month, House will wrap up its series, so almost anything can happen in these final four episodes. But tonight, as Robert Sean Leonard’s Wilson goes home with House to be administered a high-risk, against-the-odds cancer treatment, is Wilson actually at risk of dying, and leaving the show a month early? Possible. But not probable. Wilson and House, as at the end of Casablanca, deserve one closing scene together in the finale to underscore their complicated, enduring, entertaining friendship.