The film tells the story of a group of pensioners desperate to visit Le Mont-Saint-Michel.

Husband finds out that his wife is a secret agent and that she has a handsome partner.

The film is set in Marais, a quiet region along the banks of Loire river in 1918. Riton is afflicted with a bad-tempered wife and three unruly children. Garris lives alone with his recollections of World War I trenches. Their daily life consists of seasonal work and visits from their two pals: Tane, the local train conductor and Amédée, a dreamer and voracious reader of classics.

Morgan, a sensitive 12-year-old, growing up in richness and royalty, finds a true friend in Julien, a young man hired to tutor him.