You are getting sleepy... at the count of three, you will go buy tickets to Jim Carrey's next movie... and you will tell all your friends to go, too... At least, that's how Carrey hopes it will work. Variety reports that he's attached to star in ''The Hypnotist,'' a romantic comedy for Revolution Studios. He'll play a world-renowned mesmerist who isn't nearly as commanding offstage. When he loses his gifts, he's forced to woo a woman using only ordinary powers of persuasion in order to get them back. Sounds tough, but for a guy who enjoyed God-like omnipotence in his last movie, becoming a hypnotist should be a snap.