20 Euros Agatha Christie

Issued as part of the Monnaie de Paris running series honoring figures of world literature, this piece marks the centenary of Christie's The Murder of Roger Ackroyd — the 1926 novel whose unreliable narrator caused a genuine scandal in British detective fiction circles and triggered a public debate about whether the twist constituted fair play. The Detection Club, founded four years later, would codify rules of fair-play mystery writing partly in response to exactly that controversy.