Best Medicine, the highly anticipated U.S. television adaptation of the beloved British series Doc Martin, premiered on CBS in fall 2025 and has quickly become one of the most talked-about new shows of the season. Executive produced by the original creators and featuring a fresh American cast, the series reimagines the iconic story of a brilliant but socially inept doctor forced to practice in a small, quirky coastal town—this time relocated from the fictional Portwenn, Cornwall, to the picturesque seaside village of Port Harbor, Maine.

The show centers on Dr. Martin Ellingham (played by the Emmy-nominated British actor Martin Clunes, reprising his role in a rare cross-Atlantic move), a world-class vascular surgeon whose crippling phobia of blood forces him out of the operating theater and into general practice. After a disastrous attempt to continue his surgical career in Boston, Martin reluctantly accepts a position as the sole GP in Port Harbor, a tight-knit fishing community where everyone knows everyone’s business. His brusque manner, zero bedside manner, and blunt honesty immediately clash with the locals, who range from eccentric lobster fishermen to nosy shopkeepers and a fiercely independent schoolteacher named Louisa Glasson (now played by American actress Jessica Chastain in a role originally portrayed by Caroline Catz).

The adaptation stays remarkably faithful to the source material while infusing it with distinctly American flavor. Port Harbor replaces Portwenn’s quaint cobblestone streets with weathered clapboard houses, lobster traps, and foggy Atlantic mornings. The humor remains dry and character-driven, with Martin’s social awkwardness and frequent outbursts providing the comedic backbone. Early episodes introduce familiar storylines—Martin’s botched attempts at house calls, his prickly romance with Louisa, and the town’s endless stream of bizarre medical complaints—but they are recontextualized with U.S.-specific touches: debates over healthcare access, small-town opioid struggles, and the clash between old-school Yankee stoicism and Martin’s clinical precision.

Clunes’s return as Martin is a masterstroke. The actor brings the same grumpy charm and subtle vulnerability that made the original a global hit, while Chastain’s Louisa is a fiercer, more independent foil—still a teacher, but now also a single mother navigating a strained relationship with her own family. The supporting cast shines: John Slattery as the town pharmacist Bert Large, whose schemes to boost business often backfire hilariously; Allison Janney as the sharp-tongued receptionist Pauline; and a breakout performance by young actor Jacob Tremblay as Martin’s reluctant protégé, a local teen with a knack for medicine.

Critically, Best Medicine has earned strong reviews. Variety called it “a loving, faithful transplant that keeps the heart of the original while giving it new American lungs,” while The New York Times praised the “perfect balance of humor, heart, and prickly humanity.” Audience reception has been enthusiastic, with CBS reporting record viewership for the first three episodes and strong streaming numbers on Paramount+.

The series also explores deeper themes—Martin’s gradual self-awareness, the importance of community in healthcare, and the tension between individual brilliance and collective care—while maintaining the light-hearted tone that made Doc Martin a long-running success (nine seasons in the UK). Season 1, consisting of eight episodes, ends with a cliffhanger involving Louisa’s pregnancy and Martin’s ongoing battle with his phobia, setting up clear potential for renewal.

For fans of the original, Best Medicine feels like a warm homecoming with a fresh coat of paint. For new viewers, it’s an accessible, character-rich dramedy that proves some stories are timeless—no matter which side of the Atlantic they call home. In Port Harbor, the doctor may be grumpy, but the medicine—and the heart—is undeniably good.