Skip to main content
Tuesday, 25 August 2026 · Morning editionLondon ⛅ 17°C8 TV premieres this week7 prime-time slots tonightStreaming #1: Toy Story 5About UsOur TeamSourcesContactNewsletter

Cast of Cast Diagram Maths

HomeCasts

In ‘Cast Diagram Maths‘, Professor Alistair Finch (Ian McNeice) leads a team of detectives using Venn diagrams to solve crimes, starring alongside DI Laura Chen (Gemma Chan) and DS Ray Stokes (Mark Addy).

  • BBC
  • 2024
  • TV series
  • 9 cast

Main cast

  • Professor Alistair FinchIan McNeiceMain
  • DI Laura ChenGemma ChanMain
  • DS Ray StokesMark AddyMain

Supporting cast

  • DC Nina PatelNisha NayarSupp
  • DC Tom JarvisTom Rhys HarriesSupp
  • Chief Superintendent Marion BrooksEmer KennySupp
  • Dr. Helen FinchHarriet ThorpeSupp

Guest & voice

  • Lydia CraneRuthie HenshallGuest
  • DCI Ian BalfourDerek RiddellGuest

No matches — try another name.

About this cast

Cast Diagram Maths is a 2024 BBC crime drama that blends mathematics with detective work. The series follows a police unit that applies set theory and Venn diagrams to puzzling cases, examining the intersections of suspects, motives, and alibis. The show stars Ian McNeice as the brilliant but eccentric professor who heads the unit.

FAQs

Who plays Professor Alistair Finch in Cast Diagram Maths?

Ian McNeice portrays the brilliant mathematician Professor Alistair Finch.

Is Cast Diagram Maths based on a true story?

No, the series is a fictional crime drama created by writer Jack Thorne, though it draws inspiration from real police use of data analysis.

How many series of Cast Diagram Maths are there?

As of 2024, there is one series consisting of six episodes.

Where is Cast Diagram Maths filmed?

The series is filmed primarily in Manchester and the North West of England, standing in for a fictional city.

Sources & where to watch: IMDb · Wikipedia · Where to watch (JustWatch UK) · Updated June 2026

Browse all cast guides →