Best Medicine Cast: Full Actor and Character Guide for Seasons 1 and 2

The Best Medicine cast is led by Josh Charles as Dr. Martin Best, Abigail Spencer as Louisa Gavin, Annie Potts as Aunt Sarah, Josh Segarra as Sheriff Mark Mylow, and Cree as Elaine Denton. The five actors star in FOX’s American medical comedy-drama, adapted from the British series Doc Martin. The story follows a brilliant but socially awkward surgeon who leaves Boston to practice medicine in the small coastal town of Port Wenn, Maine.

The supporting cast includes Didi Conn, Clea Lewis, John DiMaggio, Carter Shimp, and Cindy De La Cruz. Season 2, which officially premiered on September 22, 2026, reunites the principal actors, promotes Stephen Spinella and Jason Veasey to series regulars, and introduces guest performers including Jack Cutmore-Scott. The show’s official cast and character information also identifies several familiar residents who help bring the fictional Maine community to life.

Best Medicine Main Cast and Characters

The Best Medicine TV show cast features experienced television stars alongside younger performers. Each main character brings something different to Martin’s life, whether it’s a family connection, a potential romance, or another challenge to his already strained patience.

Actor	Character	Role in the Series
Josh Charles	Dr. Martin Best	Former Boston surgeon who becomes Port Wenn’s local doctor
Abigail Spencer	Louisa Gavin	Local schoolteacher and Martin’s romantic interest
Annie Potts	Aunt Sarah	Martin’s aunt and a longtime member of the community
Josh Segarra	Sheriff Mark Mylow	Town sheriff and Louisa’s former fiancé
Cree	Elaine Denton	Martin’s energetic and ambitious medical assistant

Josh Charles as Dr. Martin Best

Josh Charles plays Dr. Martin Best, a gifted surgeon who leaves his successful career in Boston and moves to the Maine fishing village where he spent summers as a child.

Martin is exceptionally good at diagnosing and treating patients, but dealing with people is another matter. His blunt remarks and lack of social tact regularly upset the very residents he’s supposed to help. He also suffers from a blood phobia, which makes his work as a physician considerably more complicated.

Charles is best known to many television viewers as Will Gardner in The Good Wife. He brings a similar intensity to Martin, portraying a man who is confident in his medical abilities but struggles to understand the people around him.

Abigail Spencer as Louisa Gavin

Abigail Spencer plays Louisa Gavin, a local schoolteacher who develops a complicated romantic relationship with Martin.

Having lived in Port Wenn for years, Louisa knows its residents and understands how the community works. She’s more comfortable expressing her feelings than Martin, although that difference doesn’t always make their relationship easier.

Spencer is familiar to audiences for her role as Donna Paulsen in Suits and her starring performance in Timeless. As Louisa, she brings a more emotionally open perspective to Martin’s otherwise guarded world.

Annie Potts as Aunt Sarah

Annie Potts portrays Aunt Sarah, one of Martin’s closest family connections in Port Wenn.

Sarah has deep roots in the fishing community and works in the local lobster industry. She remembers Martin from his childhood and understands parts of his personality that other townspeople are still trying to figure out.

Although she cares about her nephew, she doesn’t always agree with how he treats people. Their relationship offers a glimpse of Martin’s family history while adding warmth and humor to the series.

Potts previously played Meemaw in Young Sheldon and Mary Jo Shively in Designing Women. Her experience with family-centered comedies is particularly well suited to Sarah’s role.

Josh Segarra as Sheriff Mark Mylow

Josh Segarra plays Sheriff Mark Mylow, Port Wenn’s local law enforcement officer and Louisa’s former fiancé.

Mark’s past relationship with Louisa makes Martin’s growing attraction to her more complicated. He’s also deeply involved in town life, often finding himself caught up in the disagreements and unusual situations surrounding its residents.

Segarra previously portrayed Adrian Chase in Arrow and Lance Arroyo in The Other Two. His comedic timing helps bring out the lighter side of Mark’s sometimes awkward circumstances.

Cree as Elaine Denton

Cree, also known as Cree Cicchino, portrays Elaine Denton, Martin’s medical assistant.

Elaine has plenty of energy and ambitions that stretch far beyond Port Wenn. She hopes to build a career as a social media personality, though her personal interests can sometimes distract her from work at the doctor’s office.

Her cheerful, outspoken personality creates an entertaining contrast with Martin’s preference for quiet, efficiency, and strict routines. Despite their differences, the two develop an important working relationship, particularly because Elaine knows about his blood phobia.

Cree’s previous acting credits include Big Sky, Mr. Iglesias, and Turtles All the Way Down.

Best Medicine Supporting Cast and Guest Stars

Port Wenn wouldn’t feel like a small town without its familiar faces. The residents run local businesses, maintain longstanding friendships, and frequently involve Martin in situations he’d rather avoid.

The notable supporting performers include:

• Stephen Spinella as Greg Garrison: Co-owner of The Salty Breeze, a local restaurant he runs with his husband, George Brady.
• Jason Veasey as George Brady: Greg’s husband and business partner. Their restaurant serves as a gathering place for Port Wenn residents.
• Didi Conn as Geneva Potter: A town councilwoman involved in community decisions and local affairs.
• Clea Lewis as Sally Mylow: Port Wenn’s pharmacist and a member of the Mylow family.
• John DiMaggio as Bert Large: A local handyman and the father of Al Large.
• Carter Shimp as Al Large: Bert’s son, who has a romantic connection with Elaine.
• Cindy De La Cruz as Jeannie: A schoolteacher who appears among the community’s recurring characters.

Greg and George become especially important in Season 2, with Spinella and Veasey moving from recurring performers to series regulars. Their expanded presence gives viewers more time with the couple and their restaurant.

The other supporting characters help establish the connections that make Port Wenn feel like a real community. Martin may prefer to keep his distance, but their lives and problems have a way of pulling him into local affairs.

Best Medicine Season 2 Cast: Who Returns and Who Joins?

The official Season 2 premiere took place on September 22, 2026, following a special preview on September 20.

All five principal actors returned for the second season: Josh Charles, Abigail Spencer, Annie Potts, Josh Segarra, and Cree.

One of the biggest casting developments involves Stephen Spinella and Jason Veasey. Both actors were promoted to series regulars, expanding the roles of Greg Garrison and George Brady. That means viewers can expect more of the married couple and their lives in Port Wenn.

Season 2 also features several recognizable guest performers:

• Jack Cutmore-Scott as Parker: A friendly but intrusive professional monitor assigned to oversee Martin’s compliance with medical board requirements. Parker appears in a multi-episode storyline and develops a romantic connection with Louisa, giving Martin another reason to dislike his presence.
• Martin Clunes as Dr. Robert Best: Martin’s father, who returns after appearing in Season 1.
• Andrea Martin as Judith: A well-meaning but troublesome resident whose appearance causes difficulties for Martin in the Season 2 premiere.
• Eliza Coupe as Dr. Eden Montgomery: A fellow physician who is romantically involved with Martin as Season 2 begins, complicating his relationship with Louisa.

Jack Cutmore-Scott’s role is especially significant because Parker’s involvement affects both Martin’s professional independence and his personal life. His multi-episode casting announcement established him as a new romantic interest for Louisa.

Andrea Martin’s appearance as Judith is also confirmed in the Season 2 premiere episode details.

Returning supporting performers include Didi Conn, Clea Lewis, John DiMaggio, Carter Shimp, and Cindy De La Cruz.

Not everyone appearing in multiple episodes is a series regular. Spinella and Veasey received permanent cast promotions for Season 2, while performers such as Cutmore-Scott and Clunes appear in guest roles.

Is the Original Doc Martin Actor in Best Medicine?

Yes. Martin Clunes, who played Dr. Martin Ellingham in the original British series Doc Martin, appears in the American adaptation as Dr. Robert Best, the father of Josh Charles’s character.

His involvement gives longtime fans a familiar connection to the British show without simply repeating his original role. In Best Medicine, Clunes becomes part of Martin Best’s family story rather than taking over as the town’s doctor.

The original Doc Martin also centers on a highly capable physician whose difficult personality creates problems in a close-knit coastal community. The American adaptation keeps that basic idea but moves the action to Maine and introduces its own relationships, characters, and conflicts.

Josh Charles remains the central character in Best Medicine, while Clunes’s guest appearances provide an enjoyable link between the two versions of the series.

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