14 people you totally forgot were on That '70s Show
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Dwayne Johnson
Do not adjust your screens: That is in fact Dwayne Johnson in fake sideburns. His hairstyle was an ode to his real-life father, pro wrestler Rocky Johnson.
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Justin Long
He played one of Fez's friends from his home country — and if you're wondering about the lack of similarities between their appearances, you're not alone. Long's character continued the running joke that no one knows exactly where Fez is from.
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Melissa Joan Hart
The Sabrina the Teenage Witch star hopped over to Fox to cameo as a girl who goes on a date with Hyde, but ends up ditching him for Fez.
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Amy Adams
The Oscar-nominated actress was a rookie back in season 2, when she showed up on the small screen as a guest at one of the gang's house parties.
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Alice Cooper
The setting: Eric Forman's dream. The characters: Hot Donna and Alice Cooper. The prop: A very real snake.
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Cole and Dylan Sprouse
After Big Daddy and Friends, the now-famous twins nabbed a role that didn't require taking turns on screen.
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Erika Christensen
Remember Pricemart, the fictional ’70s-era knockoff of Target? Well Erika Christensen spent a day pretending to work there (and getting set up with Eric… by Red).
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Jessica Simpson
What do you get when you combine Michael Kelso with Annette, his girlfriend from California who was also referred to as Blonde Jackie? You get… not nearly enough brain cells.
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Rachel Bilson
Move over, Seth Cohen. Rachel Bilson was on That '70s Show, and she was just as enamored with one Wilmer Valderrama.
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Alyson Hannigan
In between her stints on Buffy the Vampire Slayer and How I Met Your Mother, Willow-slash-Lily's alter ego played Kelso's fellow police cadet.
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Jenna Fischer
The Office star played Stacy Wanamaker, a former schoolmate of the gang. And yes, they had an offensively sexist nickname for her.
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Lindsay Lohan
During Valderrama and Lohan's short-lived but high-drama romance, she did an equally short-lived stint on her boyfriend's show. The resulting episode perfectly encapsulates 2004.
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Bruce Willis
If you had a sitcom in the early aughts and Bruce Willis didn't guest star, did you even have a sitcom at all?
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Mary Tyler Moore
The comedy legend graced the Fox show with her presence to play Christine St. George, anchor of the fictional news show What's Up Wisconsin? That '70s Show filmed on the same soundstage that was once home to Moore's eponymous series, bringing the whole thing fantastically full-circle.