L'Eglise St-Jean-Baptiste in Montrésor is (or was) a "collegiate church," which means worship services there were organized by a "college of canons" — a non-monastic community of clergymen. It was run on the model of a cathedral, but there was no bishop in residence. Saint-Aignan also has a collegiate church.
The church "looks disproportionately grand for a small village," says the author of the Cadogan guide to the Loire Valley. The college canons didn't survive the French Revolution of 1789, but the church was then and is still today the local parish church.
St-Jean-Baptiste church is basically a Gothic-style building but with important Renaissance features, including the front portal. Two Renaissance-era stained-glass windows in the church have survived to the present day.
On another subject, it seems strange to be writing this blog about life in France without mentioning the deaths of two major 20th- and 21st-century figures here: the 93-year-old author and French Academy member Jean d'Ormesson, and the 74-year-old rock-and-roll singer and master showman (bête de scène) Johnny Hallyday — "the French Elvis" as the U.S. press liked to call him. May both rest in peace.