2025-2026 TV Guest Stars Who Stole the Show And Maybe Our Hearts, Too!

Seeing your favorite actors in different roles is always entertaining.

Sometimes, it’s fun to see a fan favorite reprise a role and shake up the dynamics on a beloved show.

Other times, it’s both entertaining and challenging to see a talented actor take on a new killer role.

These guest-starring roles brought out the best in these actors’ emotional scenes.

The TV Fanatic staff compiled a list of TV guest stars from the 2025-2026 TV season that impressed us with their performances. 

These guest stars stole the show, and many stole our hearts, except for the few villains who wowed us with their talents.

Keep scrolling to read our favorite TV guest stars.

Jensen Ackles – Tracker

We couldn’t have the best guest-star list without including Jensen Ackles as Russell Shaw. He’s more like a returning guest star, but the dynamics change on Tracker in every episode he’s in.

Jensen Ackles and Justin Hartley have played their dysfunctional sibling relationship beautifully, and by the Tracker Season 3 finale, the brothers were closer and determined to learn the truth about their father.

It’s still entertaining that neither is afraid to run into action with a gun, but Russell gets answers differently. He has different connections.

Jensen Ackles excels at playing a badass who flaunts it to impress Reenie, but at his core, wants to protect his family.

Whenever Russell appears, he takes charge, alleviating some of Colter’s burden. Russell would do anything for his brother, including work for the enemy to keep a vicious family secret from surfacing.

Sam Richardson – St. Denis Medical

I might be biased because I’ve always been a huge Sam Richardson fan, but his guest star role on St. Denis Medical was a standout.

He played Michael, Ron’s son, on St. Denis Medical Season 2 Episode 12, “Nod and Agree.” 

His character was the perfect narrative foil to Ron. Michael was level-headed, whereas Ron was reactive–a sunshine to a perpetual storm cloud. 

Their contrasting personalities formed the basis of the memorable father-son conflict. 

Even though Richardson is known for being hilarious, he absolutely crushed the grounded, earnest aspect of Michael’s character. 

The final heart-to-heart between Ron and Michael brought tears to my eyes. Of course, the writers deserve credit, but Richardson has also earned my respect for delivering such a fantastic emotional performance in a sitcom. -Sam Huang

Adam Campbell – NCIS: Origins

When Donald “Ducky” Mallard shows up, everything is infinitely better. 

Fortunately for us, NCIS: Origins featured the younger version of Ducky twice during the season, and each time, he stole the show.

Campbell’s uncanny ability to capture the essence of what the late David McCallum brought to the iconic role is what viewers can cherish the most.

He makes it feel like Ducky is suspended in time, and there’s something magical about that. Ducky’s ability to charm everyone he crosses paths with, no matter their disposition, is what makes him so special.

And bringing that energy to the NCIS: Origins world brought out new sides to the characters and explored dynamics we hadn’t even dreamed of. 

When Ducky shows up on NCIS: Origins, he leaves you craving more. – Jasmine Blu

Mary Wiseman – Star Trek: Starfleet Academy

After leaping from the 23rd Century to the 32nd with the Star Trek: Discovery crew, Sylvia Tilly abandoned her command career path, finding a new passion in teaching when Starfleet Academy reopened and mentoring cadets navigating a post-Burn galaxy.

When the Star Trek: Starfleet Academy series was announced, we expected Tilly to be a regular instructor, but it was not to be. We waited. And we waited. And waited some more.

So when, on Star Trek: Starfleet Academy Season 1 Episode 8, “The Life of the Stars,” she arrives, the fanfare was real even if it wasn’t literal.

“Homework: Find a play. I’ll select one that suits our purposes. We will read it out loud, discuss, and dissect. And for those of you still bristling with confusion and/or resentment… I don’t care. Fail this, fail the semester, so get excited, little chickens! Tomorrow, we’re in the theater.” — Lt. Tilly.

And it was such an amazing return. Tilly is the kind of teacher we all dream of having. Not the nicest. Not the toughest. The kind that makes a difference.

For a class of traumatized cadets feeling beaten and hopeless, she helped them find direction and purpose. For a galaxy of Tilly Fanatics, her presence was like coming home.- Diana Keng.

Sydney Park – Will Trent

Sydney Park has portrayed Young Amanda multiple times, but when she reprised the role for the final time on Will Trent Season 4 Episode 17, she stole the show and our hearts.

Her mannerisms mirrored Sonja Sohn’s so much that it was uncanny, and you could tell that version of Amanda was just as devoted to Will.

Sydney Park could soothe our souls by bringing Amanda and Will’s relationship to the forefront right after Amanda died.

We saw how much Amanda loved Will as a baby, and that love carried over to giving him a career at the GBI.

She would have done anything to rescue him, and her Amanda allowed the series to explore deeper emotional dynamics with Will.

He finally got the closure he needed, and he and the viewers cried buckets as we said a final goodbye to Amanda Wagner.

Morgan Holmstrom – Outlander

It was always hard to guess which book storylines Outlander would run with in the final season, but we all hoped that we would see full closure for Young Ian and Emily’s story.

That came during Outlander Season 8 Episode 6, when Young Ian and Rachel set off on a journey to find out what had happened to his former Mohawk tribe, more specifically, his former wife and her children.

This created a tearful, bittersweet moment as Emily did the one thing mothers would never, ever want to do.

In an attempt to save her son, she asked Young Ian and Rachel to take him. Yes, directly from the books, but it brought tears to my eyes as I thought about the sacrifice.

Morgan Holmstrom has commanded the screen whenever she’s appeared throughout Outlander, and this time, it came with the added weight of it being her final appearance – Alexandria Ingham

Eric Dane – Brilliant Minds

Eric Dane went the extra mile and portrayed a firefighter, Matthew Ramati, who struggled with ALS and telling his family about his diagnosis.

There was not a dry eye during Brilliant Minds Season 2 Episode 9 because Matthew’s arc mirrored Dane’s real-life story.

Matthews’s story hit home because he didn’t want to burden his family, but his ex-wife, Alicia, and their daughter, Gabi, longed to be there for him through the journey.

Eric Dane played such an inspiring role by showing how important it was to have a village in caring for Matthew, who has ALS. It was the most heartfelt episode of Brilliant Minds Season 2 so far.

Dane died only a few months after this episode, showing what a fighter he truly was. He wanted everyone to be educated about ALS, and our hearts go out to him and his loved ones.

Riley Green – Marshals

It’s always a risk when you cast someone who isn’t exactly an actor into any kind of role in a successful primetime series.

But Country star Riley Green had to play a pretty heavy and intense role as Garrett, Kayce, and Cal’s very haunted comrade from their Navy SEAL days on Marshals, and Green knocked it out of the park.

Through Garrett, we got a heartbreaking exploration of what PTSD can look like and how it can deeply affect the trajectory of a person’s life when the physical war ends, but the mental one takes hold in the years that follow.

Watching Garrett find some semblance of peace was gratifying, but his struggles were always apparent.

But in many ways, his story could only ever end in tragedy, and Garrett’s disturbing yet heroic accident, followed by his quiet death, was a pivotal moment in Marshals Season 1 and even set the trajectory for where the show heads next.

Piper Perabo – The Hunting Party

It was challenging to choose only one guest star on The Hunting Party Season 2, but Piper Perabo won my heart with her portrayal of Colette Atkins.

Colette Atkins was the victim of sibling abuse, and her father was her safe haven. Perabo gave such an emotional performance when she heard the voices of her father telling her to kill her sister and not to tolerate the abuse.

After he died, she still experienced auditory hallucinations of him until the Pit took that away, allowing her only a recording of her father if she behaved.

After the explosion, Colette reverted to being a scared, lost child, and Perabo played the role with such complexity.

Colette only kidnapped men who would sing lullabies to her. It was chilling, but you couldn’t help but feel sorry for her.

Felicity Huffman – Doc

This one is totally a sneak because technically, Huffman was a series regular for the season, but it had to be mentioned anyway.

There was so much happening on Doc Season 2, and boy, did we have a great time chatting and dissecting the good, the bad, and the dramatic content they delivered to us, like the unapologetic Fanatics that we are.

But one of Doc’s biggest developments was the addition of Felicity Huffman‘s Joan Ridley. And she made one hell of an impression on the series, leaving a footprint that will carry on as long as the show does.

Joan, serving as Amy’s mentor, maternal figure, and a legendary doctor in her own right, added energy to the series and branched out into many compelling storylines, from further exploring Amy’s past to influencing her future.

Joan Ridley really was a legend played by a legend, and she was easily one of the most compelling aspects of the season as a doctor who truly lived her life in service to others and was genuinely passionate about pushing others to do the same.

She made the other characters around her better in a way that truly pays off by the season’s end.

Noah Reid – Murder in a Small Town

I love serial killer shows. Tommy Cummins has been one of my favorite serial killers, and Noah Reid and Rossif Sutherland play off each other so well.

Tommy Cummins excelled at playing cat-and-mouse games with Karl, pretending he felt remorse and that he wanted to show him and DA Soo (Jamie Chung), where the bodies were.

But Tommy was an artist, and he really wanted to showcase his prison art and showcase the bodies like trophies.

Noah Reid played Tommy with a mixture of menace and charisma, making him entertaining and keeping the audience on their toes. He was a monster, but you never guessed he’d lead Karl and DA Soo to his version of Dante’s Inferno and try to burn them alive.

Tommy’s return visit was good for something else, too. It made Karl appreciate everything he had when he almost died.

Over to you, TV Fanatics. Did your favorite guest stars make the list? Who else would you add?

Let us know below.

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