play the fool

verb2

1. •
   To behave in a foolish or comical manner.

   • Back in school again, Maxwell plays the fool again Teacher gets annoyed — 1969
2. •
   To pretend or feign ignorance.

   • I play the fool when we're together But I cry when we're apart, yeah I couldn't do you no better Don't break what's left of my broken heart, baby — 1980