10 Big-Name Stars Who Appeared on ‘CSI,’ Now 20 Years Old

CSI Guest Stars John Krasinski Viola Davis Taylor Swift
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A bevy of big-name stars appeared on CSI: Crime Scene Investigation over the years, and not all of them played good guys!

To celebrate CSI’s 20th anniversary on Tuesday, October 6, we’re looking back at 10 major celebs who appeared on the CBS procedural. We could have done entire galleries for the CSI guest stars who hail from Battlestar Galactica — e.g. Katee Sackhoff, Grace Park, James Callis, Rick Worthy, Michael Trucco, Kate Vernon — or Desperate Housewives — e.g. Marcia Cross, Neal McDonough, Brenda Strong, Richard Burgi, Steven Culp, Tuc Watkins, Beau Mirchoff, Harriet Sansom Harris — but we had to draw the line somewhere!

Mahershala Ali
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Mahershala Ali

The two-time Oscar-winning star of Moonlight and The Green Book played a security guard in the Season 3 episode “Lucky Strike.”

Justin Bieber
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Justin Bieber

Back during his moptop days, the Canadian pop star played serial killer and serial bomber Jason McCann in two Season 11 installments.

Viola Davis
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Viola Davis

The How to Get Away With Murder star and Oscar-winning actress played a defense attorney in Season 3’s “The Execution of Catherine Willows.”

America Ferrera
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America Ferrera

Before she led the casts of Ugly Betty and Superstore, Ferrera appeared as the sister of a missing girl in Season 5’s “Harvest.”

John Krasinski
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John Krasinski

This star of The Office and Jack Ryan got an unceremonious CSI appearance as an electrocuted victim in Season 5’s “Who Shot Sherlock?”

Tracee Ellis Ross
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Tracee Ellis Ross

This actress plays Laurence Fishburne’s onscreen daughter-in-law in Black-ish—but she was his onscreen ex-wife, Gloria Parkes, in four Season 11 episodes of CSI.

Liev Schreiber
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Liev Schreiber

The Ray Donovan star portrayed Michael Keppler, Grissom’s temporary replacement, in four Season 7 episodes.

Taylor Swift
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Taylor Swift

Talk about “Bad Blood”! This pop star made her acting debut in a Season 9 episode of CSI, playing Haley Jones, a teenager felled by a pair of scissors.

Milo Ventimiglia
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Milo Ventimiglia

The future Heroes and This Is Us star portrayed teenaged murderer Bobby Taylor in the fifth-ever episode of the series.

Kate Walsh
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Kate Walsh

Six months before she made her Grey’s Anatomy debut, Walsh appeared in a Season 5 episode of CSI, playing a transgender Vegas performer nicknamed Mimosa.