Alice and Peter are celebrating their retirement and are looking forward to a new phase in their lives. Then Alice finds out that her best friend Magalie, who dies completely unexpectedly, had been having an affair in France for 15 years. The confrontation with the finiteness of life plunges Peter into an existential crisis: to the great chagrin of Alice, who is a bon vivant, he becomes a total health fanatic. When Peter invites Heinz, Magalie's widowed husband, to join him on a cruise, which Alice hopes will breathe new life into a marriage, their harmonious retirement is over.