17 Memorable Guest Appearances on The Big Bang Theory
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These special guests appeared on The Big Bang Theory as themselves for some incredibly hilarious moments. Check them out!
1. Leonard Nimoy
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We begin with the recently deceased cultural icon, Leonard Nimoy. In Season 5, the Star Trek star acted as the voice of Sheldon's rather opinionated Mr. Spock action figure.
2. Summer Glau
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In Season 2, Leonard, Howard, and Raj spot Summer Glau (Firefly, Serenity, The Terminator) on a train, and promptly all make fools of themselves.
3. Charlie Sheen
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Charlie Sheen makes an appearance in Season 2, when he and Raj have a brief encounter at The Cheesecake Factory.
4. Stan Lee
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In Season 3, Sheldon manages to get a restraining order against him by Stan Lee.
5. Wil Wheaton
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Best known for his role on Star Trek: The Next Generation, Wil Wheaton has made more than a few appearances, most of which involve him antagonizing Sheldon. He made his first appearance in Season 3.
6. Neil Degrasse Tyson
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Neil Degrasse Tyson, astrophysicist and host of the show, Cosmos, appeared in Season 4.
7. Katee Sackhoff
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Best known for her role on Battlestar Galactica, Katee Sackoff appears in Howard's fantasies in Season 3.
8. George Takei
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Star Trek's George Takei appears in Season 3. In a fantasy that begins with aforementioned actress, Katee Sackoff, George Takei makes an accidental appearance (along with Bernadette).
9. LeVar Burton
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Star Trek: The Next Generation's LeVar Burton is also known for hosting "Reading Rainbow." He has made a few appearances, the first of which was in Season 4. He's even taken part in "Fun with Flags."
10. Stephen Hawking
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Scientist Stephen Hawking has appeared a few times, but Sheldon first had the chance to meet his idol in Season 5.
11. Brent Spiner
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Best known for his role on Star Trek: The Next Generation, Brent Spiner appears in Season 5 long enough to ruin Sheldon's action figure.
12. Buzz Aldrin
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Astronaut Buzz Aldrin appears in Season 6, giving out Halloween Candy and bragging about walking on the moon.
13. Howie Mandell
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In Season 6, Howie Mandell steals Howard's spotlight when he returns from space.
14. Bill Nye
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Bill Nye appeared in Season 7 as a rival to "Professor Proton," who was played by another special guest, Bob Newhart.
15. James Earl Jones
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In Season 7, Sheldon gets to hang out with James Earl Jones. Included in their activities are ice cream, a ferris wheel ride, karaoke, and even playing a prank. Which brings me to...
16. Carrie Fisher
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Also appearing in Season 7, Carrie Fisher is the victim (and that's a strong word) of a prank by Sheldon and James Earl Jones.
17. Nathan Fillion
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In Season 8, Raj and Leonard try to decide if they man they run into a deli is actually Firefly's Nathan Fillion. Of course, you might also recognize Fillion from a hit show called Castle.