TV crossovers are popular stunts during sweeps weeks. CBS is trying something wild and crazy different this week with “Two and a Half Man,” its most most popular comedy, and “CSI,” its most popular drama. The characters aren’t crossing over, the writers are. “CSI” writers Carol Mendelsohn and Naren Shankar wrote Monday’s “Two and a Half Men,” in which the boys become involved with a murder investigation. “Two and a Half Men” writers Chuck Lorre and Lee Aronsohn wrote Thursday’s “CSI,” in which the Las Vegas crew investigate the death of a sitcom diva. Lorre discussed the radical move on a media conference call:

It was a really half-assed idea when I first pitched it to Carol and the fact that it’s taken hold and we’re having this conversation now defies every sense of reality that I have. It’s mind-boggling that we actually did this.