March 2026 is a strong month for BritBox, with the platform leaning into its core strength: high-quality British crime drama and character-driven mysteries. This month features a returning detective favorite, a tense environmental thriller, a celebrated anthology’s final season, and a new installment of a long-running procedural.

If you’re searching for the complete BritBox March 2026 schedule, here is the full breakdown.

Must-Watch Highlights on BritBox in March 2026

Karen Pirie Season 2

Karen Pirie – Season 2
Karen Pirie – Season 2

Streaming March 7 | Weekly Episodes

Detective Inspector Karen Pirie returns with a new cold case that examines institutional silence and buried trauma. Based on the novels by Val McDermid, the second season follows Karen as she reopens a historic case involving political influence and conflicting witness testimony.

The series stands out for its contemporary tone, layered character development, and strong female-led perspective. Rather than focusing solely on procedural mechanics, Season 2 explores how past decisions continue to shape present-day lives.

New episodes stream weekly beginning March 7.

After the Flood

BritBox Premiere – March 14

Set in a small English town struck by a catastrophic flood, this atmospheric thriller begins when a body is discovered in an underground car park. As investigators search for answers, the disaster exposes hidden corruption and long-buried secrets within the community.

The series blends environmental tension with psychological drama. It is less about rapid twists and more about the slow unraveling of a town’s fragile stability.

All episodes become available starting March 14.

Inside No. 9 Final Season

Arrives March 21 | Weekly Episodes

The acclaimed anthology created by Reece Shearsmith and Steve Pemberton delivers its final season this month. Each standalone episode presents a self-contained story, often confined to a single location, with a sharp narrative twist.

Known for its theatrical structure, dark humor, and unpredictable endings, the final season continues the show’s tradition of genre experimentation. For longtime viewers, this marks the conclusion of one of Britain’s most inventive television series.

Episodes stream weekly beginning March 21.

Grace Season 4

Available March 28

John Simm returns as Detective Superintendent Roy Grace in the fourth season of ITV’s Brighton-set crime drama. This season introduces a complex investigation that intersects with Grace’s personal life, raising emotional stakes alongside the central mystery.

The series remains one of BritBox’s most consistent performers internationally, offering traditional British detective storytelling grounded in character and atmosphere.

Season 4 begins streaming March 28.

BritBox March 2026 Full Release Schedule

March 7
Karen Pirie Season 2 – Episode 1 (new episodes weekly)

March 14
After the Flood – Series Premiere

March 21
Inside No. 9 – Final Season Premiere (weekly episodes)

March 28
Grace Season 4 – Premiere

Throughout March:
Additional BBC and ITV library titles, selected British crime documentaries, and classic comedy additions rotate into the catalog.

What to Watch Based on Your Preferences

If you prefer modern detective investigations with emotional depth, start with Karen Pirie.

If you enjoy slow-burn thrillers centered on community secrets, After the Flood is the strongest choice.

If you appreciate anthology storytelling with clever twists, Inside No. 9 remains essential viewing.

If you favor traditional procedural crime drama, Grace delivers familiar structure with strong performances.