Bob and Greta De Jaegher have been happily married for 40 years and can look back on a rich and fulfilled life. Their two sons Steve and Carl have successful lives as well: Steve is a talented and recognised film director and Carl is a promising chef. Steve's wife Billie wrote a bestseller about happiness and wants to start a family with her husband. Meanwhile, brother-in-law Rik who works at the zoo, tries to carry on life with his kids after his wife died two years ago. To mark their 40th wedding anniversary, Bob and Greta organise a family weekend to make an important announcement. But what should have been a cheerful family gathering turns into something no one expected...