Cast of Line of Duty: Complete Characters & Actors Guide for 2026

The cast of Line of Duty is one of the biggest reasons the British crime drama became so popular. Created by Jed Mercurio, the series follows officers working within AC-12, a police anti-corruption unit investigating suspected misconduct and corruption.

Across its six seasons, Line of Duty featured a large cast, with several actors becoming closely associated with the show. From Martin Compston, Vicky McClure, and Adrian Dunbar to major guest stars such as Keeley Hawes, Stephen Graham, Kelly Macdonald, and Thandiwe Newton, the cast helped make the series a major television success.

Who Is in the Cast of Line of Duty?

The main Line of Duty cast includes actors who play the AC-12 team as well as police officers investigated during different seasons.

The central trio are Martin Compston as Steve Arnott, Vicky McClure as Kate Fleming, and Adrian Dunbar as Superintendent Ted Hastings.

• 🎭 Martin Compston plays Steve Arnott.
• 👮 Vicky McClure plays Kate Fleming.
• ⭐ Adrian Dunbar plays Ted Hastings.
• 🎬 Keeley Hawes plays Lindsay Denton.
• 👮‍♂️ Stephen Graham plays DS John Corbett.
• 🎭 Kelly Macdonald plays DCI Joanne Davidson.
• ⭐ Thandiwe Newton plays DCI Roz Huntley.
• 🎬 Craig Parkinson plays Matthew “Dot” Cottan.
• 👮 Lennie James plays Tony Gates.
• 🎭 Daniel Mays plays Sergeant Danny Waldron.
• ⭐ Anna Maxwell Martin plays DCS Patricia Carmichael.
• 🎬 Gregory Piper plays Ryan Pilkington.
• 👮 Shalom Brune-Franklin plays Chloe Bishop.
• 🎭 Rochenda Sandall plays Lisa McQueen.
• ⭐ Tommy Jessop plays Terry Boyle.
• 🎬 Aiysha Hart plays DS Sam Railston.

The large ensemble allowed the series to introduce new suspects, investigators, and witnesses while keeping AC-12 at the centre of the story.

Martin Compston as Steve Arnott

Martin Compston plays Detective Sergeant Steve Arnott, one of the most important characters in Line of Duty. Steve joins AC-12 after refusing to take part in a cover-up involving an armed operation.

His character becomes a key investigator throughout the series.

• 👮 Steve Arnott is an AC-12 officer.
• 🎭 Martin Compston plays the character.
• 🔎 He investigates suspected police corruption.
• 🤝 He works closely with Kate Fleming.
• ⭐ He reports to Ted Hastings.
• 🧩 He becomes involved in complex investigations.
• ⚖️ Steve often focuses on evidence.
• 🚔 His career is shaped by difficult cases.
• 🕵️ He questions suspects during investigations.
• 📁 He works on sensitive police files.
• 🎬 His character appears throughout the series.
• 📺 Martin Compston became strongly associated with the role.
• 👥 Steve develops professional relationships with other officers.
• 🔍 His investigations often reveal new clues.
• 🧠 He is persistent during interviews.
• ⭐ He remains one of the show’s best-known characters.

Steve’s determination and sometimes impulsive approach make him an important part of the AC-12 team.

Vicky McClure as Kate Fleming

Vicky McClure plays Kate Fleming, a highly skilled detective who becomes one of AC-12’s central investigators.

Kate is known for her strong investigative instincts and ability to work undercover when necessary.

• 👮 Kate Fleming is a detective.
• 🎭 Vicky McClure plays Kate.
• 🔎 She is an experienced investigator.
• 🕵️ She works on complex police cases.
• 🤝 Kate works closely with AC-12 colleagues.
• ⭐ She is one of the show’s central characters.
• 🚔 Her police career develops across the series.
• 🧩 She investigates difficult suspects.
• 📁 She studies evidence carefully.
• 👥 She builds professional relationships.
• 🎬 Her character appears across multiple seasons.
• 🧠 Kate is calm during many investigations.
• 🔍 She notices important details.
• ⚖️ She takes police integrity seriously.
• 📺 Vicky McClure became closely identified with the role.
• ⭐ Kate is a key figure in the Line of Duty story.

Kate’s investigative skills make her an important counterbalance to Steve’s more direct approach.

Adrian Dunbar as Ted Hastings

Adrian Dunbar plays Superintendent Ted Hastings, the senior officer leading AC-12.

Ted is known for his strong personality, memorable expressions, and determination to uncover police corruption.

• 👮 Ted Hastings leads AC-12.
• 🎭 Adrian Dunbar plays Hastings.
• ⭐ He is one of the show’s central characters.
• 🔎 He investigates police corruption.
• 📁 Ted oversees major cases.
• 🤝 He works with Steve Arnott.
• 🤝 He works with Kate Fleming.
• 🚔 He has extensive police experience.
• ⚖️ Integrity is important to his character.
• 🧩 His decisions affect major investigations.
• 🎬 He appears throughout the series.
• 📺 His character became widely recognised.
• 🗣️ Ted is known for memorable speeches.
• 🕵️ He questions senior officers.
• 🏢 AC-12 is central to his professional life.
• ⭐ Adrian Dunbar’s performance is a major part of the show’s appeal.

Ted Hastings provides the leadership and authority that hold the AC-12 team together.

Keeley Hawes as Lindsay Denton

Keeley Hawes plays Detective Inspector Lindsay Denton in the second season. Denton becomes the focus of an AC-12 investigation after her actions during a police operation raise serious questions.

Her storyline became one of the show’s most memorable investigations.

• 👮 Lindsay Denton is a senior police officer.
• 🎭 Keeley Hawes plays Denton.
• 🔎 AC-12 investigates her conduct.
• 🚔 Her character is involved in a major operation.
• 🧩 Her story contains many unanswered questions.
• ⚖️ The investigation examines police procedures.
• 🕵️ Steve Arnott works on the case.
• 👮 Kate Fleming is also involved.
• ⭐ Denton becomes a major season-two character.
• 🎬 Keeley Hawes received strong attention for the role.
• 📺 Her storyline adds complexity to the series.
• 🔍 AC-12 searches for evidence.
• 🧠 Denton is an intelligent and complicated character.
• 📁 Her case develops through multiple interviews.
• 🎭 The performance adds tension to the season.
• ⭐ Denton remains a memorable character in Line of Duty.

Her story helped establish the series’ pattern of presenting complicated suspects rather than simple heroes and villains.

Stephen Graham as John Corbett

Stephen Graham plays Detective Sergeant John Corbett in season five. Corbett is an undercover officer whose investigation becomes increasingly complicated.

The character is central to one of the show’s most tense storylines.

• 👮 John Corbett is an undercover police officer.
• 🎭 Stephen Graham plays Corbett.
• 🕵️ He works deep undercover.
• 🔎 His investigation involves organised crime.
• 🧩 His position becomes increasingly dangerous.
• 🚔 AC-12 becomes involved in his case.
• ⭐ Corbett is a major season-five character.
• 📁 His undercover work creates difficult questions.
• 🤝 He interacts with several criminal figures.
• 🎬 Stephen Graham brings experience to the role.
• 🧠 Corbett is determined to complete his investigation.
• ⚖️ His actions raise questions about police methods.
• 🔍 AC-12 searches for the truth.
• 📺 His storyline adds suspense.
• 🎭 The character has a complicated relationship with authority.
• ⭐ Corbett is one of the series’ memorable later characters.

Stephen Graham’s performance added another layer to the show’s exploration of undercover policing.

Kelly Macdonald as Joanne Davidson

Kelly Macdonald plays Detective Chief Inspector Joanne Davidson in season six. She becomes the subject of an AC-12 investigation involving a complicated murder case.

Her character is at the centre of the show’s final completed season.

• 👮 Joanne Davidson is a senior detective.
• 🎭 Kelly Macdonald plays Davidson.
• 🔎 AC-12 investigates her team.
• 🧩 Her case involves a murder investigation.
• 🚔 Davidson leads a major police operation.
• ⭐ She is the main focus of season six.
• 📁 Her team contains several secrets.
• 🕵️ AC-12 examines police conduct.
• 🤝 Steve Arnott works on the investigation.
• 👮 Ted Hastings remains important to AC-12.
• 🎬 Kelly Macdonald gives a detailed performance.
• 🧠 Davidson is a complex character.
• ⚖️ The investigation raises questions about police integrity.
• 🔍 Evidence develops throughout the season.
• 📺 Her storyline continues the show’s central theme.
• ⭐ She is one of the most important later characters.

Davidson’s investigation continues the show’s tradition of placing a senior police officer under intense scrutiny.

Thandiwe Newton as Roz Huntley

Thandiwe Newton plays DCI Roz Huntley in season four. Huntley leads a major murder investigation while AC-12 begins examining concerns about her conduct.

Her storyline brings a new investigative team into the series.

• 👮 Roz Huntley is a detective chief inspector.
• 🎭 Thandiwe Newton plays Huntley.
• 🔎 AC-12 investigates her conduct.
• 🕵️ Her team investigates serious crimes.
• 🧩 Her storyline contains multiple mysteries.
• 📁 Evidence becomes important to the case.
• ⚖️ Police integrity is a central issue.
• 🚔 Huntley is an experienced detective.
• ⭐ She is the main focus of season four.
• 🎬 Thandiwe Newton leads the season’s guest cast.
• 🧠 Huntley is a complicated character.
• 🔍 AC-12 searches for inconsistencies.
• 🤝 She interacts with several police colleagues.
• 📺 Her investigation develops over the season.
• 🎭 Her performance adds tension to the story.
• ⭐ Huntley is one of the show’s major suspects.

Season four uses Huntley’s case to explore how pressure, ambition, and police investigations can collide.

Craig Parkinson as Dot Cottan

Craig Parkinson plays Matthew “Dot” Cottan, a detective whose story becomes increasingly important as the series develops.

Dot is closely connected to several major plot developments.

• 👮 Dot Cottan is a police detective.
• 🎭 Craig Parkinson plays Dot.
• 🔎 His character appears early in the series.
• 🧩 His story develops over several episodes.
• 🚔 Dot works within major investigations.
• ⭐ He becomes important to the wider corruption story.
• 👥 He interacts with AC-12 officers.
• 📁 His professional decisions attract attention.
• 🕵️ His actions are examined closely.
• 🎬 Craig Parkinson became strongly associated with the role.
• 🧠 Dot is a complicated character.
• ⚖️ His storyline explores police loyalty.
• 🔍 Evidence becomes important to his story.
• 📺 His character has a major impact on the series.
• 🎭 His performance adds suspense.
• ⭐ Dot remains one of the show’s most discussed characters.

Dot’s storyline is an important part of the show’s larger mystery surrounding organised police corruption.

Anna Maxwell Martin as Patricia Carmichael

Anna Maxwell Martin plays DCS Patricia Carmichael, a senior officer introduced during the later part of the series.

Carmichael is confident, direct, and willing to challenge AC-12.

• 👮 Patricia Carmichael is a senior detective.
• 🎭 Anna Maxwell Martin plays Carmichael.
• 🔎 She becomes involved in major investigations.
• 🏢 She holds a senior police position.
• ⚖️ She challenges AC-12.
• ⭐ Her arrival changes the balance of power.
• 🧩 She becomes important to the wider story.
• 📁 She examines police investigations closely.
• 🚔 She has considerable authority.
• 🗣️ Carmichael is direct during interviews.
• 🎬 Anna Maxwell Martin brings a strong presence to the role.
• 🧠 She is confident and experienced.
• 🔍 Her decisions influence later events.
• 📺 She appears in the later seasons.
• 👥 She interacts with Hastings and other AC-12 officers.
• ⭐ Carmichael is an important later addition to the cast.

Her character adds another layer of tension between different parts of the police organisation.

Line of Duty Supporting Cast

Alongside its leading actors, Line of Duty has featured many supporting performers who helped create its detailed police world.

These characters often become important to individual investigations.

• 🎭 Lennie James plays Tony Gates.
• 🎭 Gina McKee plays Jackie Laverty.
• 🎭 Kate Ashfield plays Jools Gates.
• 🎭 Jason Watkins plays Simon Banks.
• 🎭 Daniel Mays plays Danny Waldron.
• 🎭 Tommy Jessop plays Terry Boyle.
• 🎭 Rochenda Sandall plays Lisa McQueen.
• 🎭 Gregory Piper plays Ryan Pilkington.
• 🎭 Shalom Brune-Franklin plays Chloe Bishop.
• 🎭 Aiysha Hart plays Sam Railston.
• 🎭 Martin Compston plays Steve Arnott.
• 🎭 Vicky McClure plays Kate Fleming.
• 🎭 Adrian Dunbar plays Ted Hastings.
• 🎭 Kelly Macdonald plays Joanne Davidson.
• 🎭 Thandiwe Newton plays Roz Huntley.
• 🎭 Stephen Graham plays John Corbett.

The supporting cast is one reason each investigation feels different while remaining connected to the wider story.

Line of Duty Cast by Season

Each season introduces new major characters while continuing the AC-12 storyline.

The changing cast allows the show to investigate a different police case while maintaining its central characters.

• 📺 Season 1 focuses on Tony Gates.
• 🎭 Lennie James leads the first season’s guest cast.
• 📺 Season 2 focuses on Lindsay Denton.
• 🎭 Keeley Hawes plays Denton.
• 📺 Season 3 features Daniel Mays as Danny Waldron.
• 🎭 Daniel Mays leads the season’s key new storyline.
• 📺 Season 4 focuses on Roz Huntley.
• 🎭 Thandiwe Newton plays Huntley.
• 📺 Season 5 introduces John Corbett.
• 🎭 Stephen Graham plays Corbett.
• 📺 Season 6 focuses on Joanne Davidson.
• 🎭 Kelly Macdonald plays Davidson.
• ⭐ Ted Hastings remains central across the series.
• ⭐ Steve Arnott remains a key investigator.
• ⭐ Kate Fleming remains an important AC-12 figure.
• 📺 The changing suspects keep each season fresh.

This structure makes the show easy to follow while giving every season its own central investigation.

Line of Duty Main Cast and Characters

The main cast can be easier to remember when each actor is connected with their character and role in AC-12.

• 🎭 Martin Compston — Steve Arnott: AC-12 detective.
• 🎭 Vicky McClure — Kate Fleming: Detective and AC-12 investigator.
• 🎭 Adrian Dunbar — Ted Hastings: AC-12 superintendent.
• 🎭 Craig Parkinson — Dot Cottan: Detective with a major storyline.
• 🎭 Keeley Hawes — Lindsay Denton: Main suspect in season two.
• 🎭 Daniel Mays — Danny Waldron: Central character in season three.
• 🎭 Thandiwe Newton — Roz Huntley: Main focus of season four.
• 🎭 Stephen Graham — John Corbett: Undercover officer in season five.
• 🎭 Kelly Macdonald — Joanne Davidson: Main focus of season six.
• 🎭 Anna Maxwell Martin — Patricia Carmichael: Senior detective.
• 🎭 Lennie James — Tony Gates: Main focus of season one.
• 🎭 Gregory Piper — Ryan Pilkington: Recurring character.
• 🎭 Rochenda Sandall — Lisa McQueen: Character in season five.
• 🎭 Tommy Jessop — Terry Boyle: Recurring character.
• 🎭 Shalom Brune-Franklin — Chloe Bishop: AC-12 investigator.
• 🎭 Aiysha Hart — Sam Railston: Police detective.

Together, these performers form the core of one of Britain’s best-known police dramas.

Line of Duty Cast FAQs

• ❓ Who is the main cast of Line of Duty? Martin Compston, Vicky McClure, and Adrian Dunbar are the three central cast members, playing Steve Arnott, Kate Fleming, and Ted Hastings.
• 🎭 Who plays Steve Arnott? Martin Compston.
• 👮 Who plays Kate Fleming? Vicky McClure.
• ⭐ Who plays Ted Hastings? Adrian Dunbar.
• 🎬 Who plays Lindsay Denton? Keeley Hawes.
• 🎭 Who plays Roz Huntley? Thandiwe Newton.
• 👮 Who plays John Corbett? Stephen Graham.
• 🎭 Who plays Joanne Davidson? Kelly Macdonald.
• ⭐ Who plays Patricia Carmichael? Anna Maxwell Martin.
• 🎬 Who plays Dot Cottan? Craig Parkinson.
• 👮 Who plays Tony Gates? Lennie James.
• 🎭 Who plays Danny Waldron? Daniel Mays.
• 📺 How many seasons of Line of Duty are there? There are six completed seasons.
• 🕵️ What is Line of Duty about? It follows police officers investigating corruption and misconduct within the police service.
• ⭐ Who are the AC-12 officers? The best-known AC-12 characters are Ted Hastings, Steve Arnott, and Kate Fleming, with other officers joining the team over time.
• 📺 Is the original cast in every season? The main AC-12 characters continue across the series, while each season introduces different major guest characters.

Conclusion:

The cast of Line of Duty is central to the show’s success. Martin Compston, Vicky McClure, and Adrian Dunbar form the core trio as Steve Arnott, Kate Fleming, and Ted Hastings, while actors such as Keeley Hawes, Thandiwe Newton, Stephen Graham, Kelly Macdonald, Craig Parkinson, and Anna Maxwell Martin lead major storylines across the six seasons.

One of the show’s strengths is its changing cast. Each season introduces new officers, suspects, and investigations while keeping the AC-12 team at the heart of the story. That combination gives Line of Duty its distinctive mix of police investigations, tense interviews, complicated characters, and long-running mysteries.