Date Published: September 13, 2024 — Puzzle setter John Ludwig Taylor’s (David Mitchell) life of solitude is upended when his identical twin, DCI James Taylor, disappears.

Drafted in by his sister-in-law Lucy (Anna Maxwell Martin), John reluctantly assumes his brother’s identity as a detective in the Cambridge Police Authority in order to find clues to his brother’s whereabouts.

Watch Ludwig on iPlayer and BBC One from Wednesday 25 September.