Celebs On ‘Grey’s Anatomy’ — Photos Of Guest Stars

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October 5, 2017 3:07PM EDT

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Mandy Moore played Mary Portman, a patient that got trapped inside with Bailey during the hospital shooting.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Way before she was Eleven, Millie Bobby Brown played Ruby in a ‘Greys Anatomy’ season 11 episode.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Sarah Paulson played the younger Ellis Grey. Iconic.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Demi Lovato played Hayley, a girl who had a hole in her ear drum and could hear everything happening in her body, which was making her freak out.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — In a two-part episode, Christina Ricci played the paramedic who stuck her hand inside a man’s body and prevented the bomb inside him from going off.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Kyle Chandler was the head of the bomb squad who helped Meredith after she put her hand on the bomb. He ended up getting blown to bits. Even though he was only in a few episodes, his character is one we’ll never forget.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Mae Whitman guest-starred as Heather, a girl with a syndrome that made her walk at a 90-degree angle.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Baby Abigail Breslin played a young girl who had a genetic condition that wouldn’t let her feel pain.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Vanessa Marano played a sexual assault victim in 2012.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — ‘Gilmore Girls’ alum and ‘HTGAWM’ murder star Liza Weil played a cancer patient who became friends with Izzie.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — ‘Friday Night Lights’ star Jesse Plemmons played a patient with ‘lionitus,’ a bone disorder that led to facial disfiguration. Despite Derek’s best efforts, the patient died in surgery.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Before she was Offred, Elisabeth Moss played an overprotective daughter in an episode of ‘Grey’s Anatomy.’

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — ’13 Reasons Why’ star Dylan Minnette played the kid Mark Sloan made ears for!

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — ‘One Tree Hill’ star Hilarie Burton played Lauren Boswell, a doctor Arizona ends up having a one night stand with.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Wilmer Valderrama played a guitar player who had brain surgery to stop a hand tremor. He fell in love with Stephanie, but they were not meant to be. He ended up dying!

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Keke Palmer played a young woman who wanted to get put on Cristina Yang’s trial after being diagnosed with a heart syndrome. However, Keke’s character was pregnant, so Cristina had to turn her away.

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Bellamy Young guest-starred on ‘Grey’s Anatomy’ way before she played Mellie Grant on ‘Scandal!’

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — ‘Thor: Ragnarok’ star Tessa Thompson played Richard Webber’s niece!

(Courtesy of ABC)

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Stars You Forgot Were On ‘Grey’s Anatomy’

Stars You Forgot Were On ‘Grey’s Anatomy’ — Neve Campbell showed up in Seattle to play one of Derek’s sisters, Liz.

(Courtesy of ABC)

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