This year marks two decades sinceGrey’s Anatomyfirst debuted on our small screens.

Here are 10 actors who guest starred onGrey’s Anatomythat you might have forgotten about, ranked.

During her prom, Camille falls unconscious while having sex for the first time.

A collage of characters posing for the poster for Grey’s Anatomy Season 21

Image via ABC

Lizzie’s relationship with a newly pregnant Meredith Grey (Ellen Pompeo) isn’t smooth sailing at first.

Lizzie, understandably, wants Meredith to make an effort to include her in her brother’s life.

Campbell’s presence is immediately intimidating, making Lizzie a dynamic powerhouse of a professional woman.

Grey’s Anatomy Poster

When the terrified, exhausted girl can’t go on, Meredith takes Hannah’s place.

That leads Cristina to reject Sheryll without knowing her situation a young woman facing motherhood all alone.

Thankfully, Shane Ross (Gaius Charles) helps Sheryll deliver a healthy baby.

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Not even Miranda Bailey (Chandra Wilson) can resist his earnest approach he trick-or-treats for his ears!

or his cheeky smile.

3Rachel Brosnahan

Season 9, Episode 14

Yes, it’sThe Marvelous Mrs. Maiselherself!

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Asudden earthquake causes dozens of injuriesacross Seattle, but not everyone affected can make it to the hospital.

Ruby (Brown), an 11-year-old girl, is trapped at home with her unconscious mother.

Keep Reading:‘Greys Anatomy’ Needs To Bring Back These Characters At Least Once

Tessa Thompson as Camille Travis in an evening gown in a hospital bed, looking serious in Grey’s Anatomy.

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Neve Campbell as Dr. Lizzie Shepherd talks to other doctors in the hospital on Grey’s Anatomy.

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Kyle Chandler as Dylan Young looks at a doctor in scrubs with X-rays in the background on Grey’s Anatomy.

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Christina Ricci as Hannah Davies works with Ellen Pompeo as Dr. Meredith Grey in the OR on Grey’s Anatomy.

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Sarah Paulson as Dr. Ellis Grey looks perplexed at something off-screen in Grey’s Anatomy.

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Keke Palmer as Sheryll Jeffries holds a small baby and cries in a hospital bed in Grey’s Anatomy.

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A young Dylan Minnette as Ryan wearing a hearing device and looking off-camera in Grey’s Anatomy.

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Rachel Brosnahan as Brian Weston poses for a photo with a doctor and a friend in a hospital in Grey’s Anatomy.

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Elisabeth Moss as Nina Rogerson looks at something off camera with a serious expression on Grey’s Anatomy.

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A young Millie Bobby Brown as Ruby looks sad and talks to Kevin McKidd as Dr. Owen Hunt in Grey’s Anatomy.

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Grey’s Anatomy

Ellen Pompeo