1. While waiting backstage at the Ellen show, Bruno pretended he needed a nurse for throat issues.
2. When she arrived, he followed Ellen’s instructions on what to say and do, given to him live through an earpiece.
3. Obviously, Ellen being Ellen, that meant he was doing some pretty absurd things.
4. Somehow (very impressively) he kept a straight face through it all, and convinced the nurse that he was actually insane.
And luckily she was a good sport.