Memorable Guest Appearances on 'Grey's Anatomy': From Demi Lovato to Millie Bobby Brown and Beyond

Some guest stars on Grey's Anatomy had recurring roles, while others only appeared in one episode.

For instance, Demi Lovato had a brief role in a single episode during season 6. On the other hand, Millie Bobby Brown made an appearance in a season 11 episode called "I Feel the Earth Move" when she was still a relatively unknown actress.

Jeffrey Dean Morgan made his debut on the medical drama during season 2 in 2006, playing the character of Denny. He appeared in a total of 23 episodes as Izzie's love interest, with appearances in season 3 and a final appearance in season 5.

Fast forward four seasons, and Jeffrey's real-life wife, Hilarie Burton, joined the show as Dr. Lauren Boswell. During her three-episode arc, she had a brief romance with Dr. Arizona Robbins, which caused some excitement among fans who were used to seeing Arizona with Dr. Callie Torres.

Keep scrolling to see which other stars made guest appearances on Grey’s Anatomy over the years:

Grey Anatomy Guest Stars Over the Years

Credit: Getty Images (3)

Iconic 'Grey's Anatomy' Guest Stars Over the Years: Demi Lovato, Millie Bobby Brown and More

Some stars had recurring roles on Grey's Anatomy, while others only appeared in one episode.

For instance, Demi Lovato had a one-time role in season 6. In contrast, Millie Bobby Brown was not well-known when she guest-starred in a season 11 episode called "I Feel the Earth Move."

Jeffrey Dean Morgan made his debut on the medical drama during season 2 in 2006, portraying the character Denny. He became Izzie's (Katherine Heigl) love interest and appeared in a total of 23 episodes, with his last appearance being in season 5 after also appearing in season 3.

In a twist of fate, Jeffrey's real-life wife, Hilarie Burton, joined the show four seasons later as Dr. Lauren Boswell. During her three-episode arc, she had a brief fling with Dr. Arizona Robbins (Jessica Capshaw), causing a stir among fans who were invested in the relationship between Arizona and Dr. Callie Torres (Sara Ramírez).

Keep scrolling to see which other stars made guest appearances on Grey’s Anatomy over the years:

Grey Anatomy Guest Stars Over the Years

Credit: Getty Images (3)

Iconic 'Grey's Anatomy' Guest Stars Over the Years: Demi Lovato, Millie Bobby Brown and More

Multiple stars have made appearances on Grey’s Anatomy, with some staying for extended periods while others only appearing in one episode.

For instance, Demi Lovato had a brief role in a single episode of season 6. Similarly, Millie Bobby Brown was not widely recognized when she appeared in a season 11 episode called “I Feel the Earth Move.”

Jeffrey Dean Morgan made his debut on the medical drama during season 2 in 2006, playing the character Denny. He appeared in a total of 23 episodes as the love interest of Izzie (Katherine Heigl), with his last appearance being in season 5 after also appearing in season 3.

Fast forward four seasons, Morgan's real-life wife, Hilarie Burton, joined the show as Dr. Lauren Boswell. In her three-episode arc, she had a brief romance with Dr. Arizona Robbins (Jessica Capshaw), causing a stir among fans who were invested in the relationship between Arizona and Dr. Callie Torres (Sara Ramírez).

Keep scrolling to see which other stars made guest appearances on Grey’s Anatomy over the years:

Jeffrey Dean Morgan Stars You Forgot Have Appeared on Greys Anatomy

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Jeffrey Dean Morgan

Before his role as a main character on AMC's The Walking Dead, Morgan played Denny Duquette on season 2 of the ABC series. He also made appearances as a ghost or memory in seasons 3 and 5, haunting Dr. Izzy Stevens (Heigl), his love interest in the hospital. They even got engaged before Denny passed away due to complications from a heart transplant.

Kyle Chandler Stars You Forgot Have Appeared on Greys Anatomy

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Kyle Chandler

The actor from Friday Night Lights portrayed bomb squad leader Dylan Young in four episodes during seasons 2 and 3. Following his character's demise, Dylan made a return as one of Dr. Meredith Grey's hallucinations.

Christina Ricci Stars You Forgot Have Appeared on Greys Anatomy

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Christina Ricci

Ricci's storyline in season 2 as paramedic Hannah Davies was full of intense moments. In one of the episodes, she found herself in a nerve-wracking situation where she had to keep her hand inside a patient's chest cavity because there was a bomb inside him.

Elisabeth Moss Stars You Forgot Have Appeared on Greys Anatomy

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Elisabeth Moss

During her season 3 appearance on The Handmaid’s Tale, the actress didn’t portray a patient. She took on the role of Nina Rogerson, the daughter of a woman who needed surgery for her rare muscle condition.

Demi Lovato Stars You Forgot Have Appeared on Greys Anatomy

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Demi Lovato

In season 6, a former Disney Channel star appeared as Alex in a cameo role. In the episode "Shiny Happy People," Alex learns that a rare condition in her inner ear is the reason behind her self-inflicted injuries.

Sarah Paulson Stars You Forgot Have Appeared on Greys Anatomy

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Sarah Paulson

The Emmy-winning actress portrayed a younger version of Dr. Ellis Grey on season 6’s “The Time Warp.”

Mandy Moore Stars You Forgot Have Appeared on Greys Anatomy

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Mandy Moore

The actress from A Walk to Remember, Mandy Moore, made guest appearances in four episodes of season 7, starting with "Death and All His Friends" in 2010. She portrayed Mary Portman, a patient who visits the hospital several times to address issues with her colostomy bag. In her final episode, Moore's character does not wake up after surgery and has to be removed from life support.

Scott Foley Stars You Forgot Have Appeared on Greys Anatomy

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Scott Foley

The actor from Scandal played the character Henry Burton in 15 episodes of the medical drama during seasons 7 and 8. Henry ended up marrying Dr. Teddy Altman (played by Kim Raver) in order to access her medical insurance and undergo surgery. Their relationship was initially just friendly, but it evolved into a romantic one before Henry passed away.

Hilarie Burton Stars You Forgot Have Appeared on Greys Anatomy

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Hilarie Burton

During season 9, Hilarie Burton, known for her role in One Tree Hill, portrayed Dr. Lauren Boswell, a consulting craniofacial surgeon. In her three-episode appearance, Burton's character had a short-lived romantic involvement with Dr. Arizona Robbins (played by Capshaw), culminating in a single night together.

Hector Elizondo Stars You Forgot Have Appeared on Greys Anatomy

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Hector Elizondo

The Princess Diaries actor had a five-episode arc during season 10 as Dr. Callie Torres’ (Ramírez) father, Carlos Torres.

Millie Bobbie Brown Stars You Forgot Have Appeared on Greys Anatomy

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Millie Bobby Brown

Millie Bobby Brown, known for her role in Enola Holmes, delivered a strong performance in season 11. She portrayed Ruby, an 11-year-old girl who saves her mother's life by performing a tracheotomy with guidance over the phone.

Wilmer Valderrama Stars You Forgot Have Appeared on Greys Anatomy

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Wilmer Valderrama

During Season 12 of the show, the actor from That '70s Show played the role of Kyle Diaz. He portrayed a musician dealing with Multiple Sclerosis (MS) and had a romantic relationship with surgical resident Stephanie Edwards (played by Jerrika Hinton).

Josh Radner Stars You Forgot Have Appeared on Greys Anatomy

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Josh Radnor

The How I Met Your Mother alum had a brief role as Meredith’s blind date, John, during season 15’s “Momma Knows Best” episode.

Alyssa Milano Stars You Forgot Have Appeared on Greys Anatomy

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Alyssa Milano and Holly Marie Combs

The actresses who used to star in Charmed came together again on season 16 of the ABC show. This time, they played sisters named Haylee (Milano) and Heidi Peterson (Combs). In the story, their sibling is in the hospital with a tragic brain injury after a fall at a construction site. Fans will remember them as Phoebe and Piper Halliwell from the magical series that aired from 1998 to 2006.

Beanie Feldstein Grey Anatomy Guest Stars Over the Years

Credit: ABC

Beanie Feldstein

The actress portrayed Tess Desmond, an intern who who was later revealed to be a patient who was given the chance to shadow the doctors during her time at Grey Sloane.

Editor's P/S:

The article provides a comprehensive list of notable guest stars who have graced the screens of "Grey's Anatomy" over the years. From brief cameos to multi-episode arcs, these actors and actresses have brought depth and intrigue to the medical drama. Jeffrey Dean Morgan's portrayal of Denny, Izzie's ill-fated love interest, remains a fan favorite, while Millie Bobby Brown's guest appearance as a young girl performing an emergency tracheotomy showcased her exceptional talent.

The article also highlights the real-life connection between Jeffrey Dean Morgan and Hilarie Burton, who joined the show as Dr. Lauren Boswell and had a brief romance with Dr. Arizona Robbins. This storyline sparked excitement among fans who had become accustomed to seeing Arizona with Dr. Callie Torres. Overall, the guest stars on "Grey's Anatomy" have played a vital role in enriching the show's narrative, adding emotional weight and showcasing the diverse talents of the entertainment industry.