Cadfael

Cadfael (1994–1998) is a British crime drama series based on the Cadfael books by Ellis Peters. Starring Derek Jacobi, the series follows Brother Cadfael, a Benedictine monk and former crusader, as he investigates murders and mysteries in 12th-century England. Set during a period of political unrest, the series combines criminal investigations with historical settings and medieval life.

Från IMDB:
The medieval era cases of a Crusader-turned-Monk who investigates mysteries in the Norman English town of Shrewsbury.