6:42 AM PST 12/21/2012 by THR Staff
Getty
Jerry Seinfeld delighted the audience of Thursday's edition of Late Night With Jimmy Fallon when he made a surprise cameo in a re-enactment of the famous Abbott & Costello "Who's on First" sketch.
Also in the bit: that night's guest, Billy Crystal; Fallon (as Abbott); and two members of the Late Night staff, announcer Steve Higgins (as Costello) and head writer A.D. Miles.
Watch the shenanigans below.
