The 27-year-old actress and the 28-year-old actor was joined in the pic by Mark Salling and director/producer/writer Paris Barclay.
“Making Glee 100 w/ @MarkSalling @DiannaAgron & #chacecrawford,” Paris tweeted with a pic.
In case you didn’t know, Gwyneth Paltrow, Heather Morris, Harry Shum Jr., Amber Riley, and Kristin Chenoweth are also scheduled to make an appearance on the two-part episode, which will air March 18 and 25 on Fox.
Bigger pic inside… More Here! »