It's hard to believe that the series finale of Chuck aired over four years ago! No one could make us laugh quite like Zachary Levi in that show.

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Over the course of the show's five seasons, plenty of celebrities guest starred in an episode. Scroll down to see 12 celebs you totally forgot were a part of the series.

Olivia Munn (Greta)

olivia munn on chuck
NBC

Stacy Keibler (Captain Victoria Dunwoody)

stacy keibler on chuck
NBC via Getty Images

Nicole Richie (Heather Chandler)

nicole richie on chuck
NBC

Rachel Bilson (Lou)

rachel bilson on chuck
NBC via Getty Images

Danny Pudi (Vali Chandrasekaren)

danny pudi on chuck
NBC via Getty Images

Gary Cole (Jack Burton)

gary cole on chuck
NBC via Getty Images

Jenny McCarthy (Sylvia Arculin) and Andy Richter (Brad White)

jenny mccarthy and andy richter on chuck
NBC via Getty Images

Matt Bomer (Bryce Larkin)

matt bomer on chuck
NBC via Getty Images

Ben Savage (Mark Ratner)

ben savage on chuck
NBC

Michael Strahan (Mitt)

michael strahan on chuck
NBC

Steve Austin (Hugo Panzer)

steve austin on chuck
NBC