Julia Louis-Dreyfus and Jon Favreau go way back, all the way to his pre-'Swingers' days when Favreau played an angry clown on a 'Seinfeld' episode.

The two actors reminisced on the 'Tonight Show' (weeknights, 11:35PM ET on NBC) -- and got so carried away that Jay Leno didn't feel needed.

"I remember you were very serious playing the part of the serious clown," said Louis-Dreyfus. "I was scared of you... I actually thought you hated me." Responded Favreau, "I was probably just intimidated."

"Listen, I'll just let you two kids talk," joked Leno, who then got up and walked away from his desk.