Heidi Klum, Anna Kendrick, Zach Braff, Josh Groban, Rob Delaney, Olivia Wilde and Dwayne "The Rock" Johnson all got into it on Twitter. It was a brutal, bitter, no-holds-barred affair.
At the Kennedy Center Honors, Anna Kendrick performed a tune from the 1962 film Two For the Seesaw, in honor of its star, Shirley MacLaine.
She says #ItDefiesLogic
Check out her full Instagram.