Season 1 of Thicker Than Water premiered on January 27, 2014.

When their mother asks them to visit, the siblings Lasse, Oskar and Jonna return to the family's lodging house on the island of Sunnanö, a place that, for them, all means conflict and buried secrets.

Season 2 of Thicker Than Water premiered on October 17, 2016.

Season 3 of Thicker Than Water premiered on March 20, 2020.

Three years have passed since last season, and the Waldemar family are reunited in Åland after the boarding house burned down. Together, they try to get it ready to sell, but conflicts create another problem for the family.