Hearts of Soul was formed by three Harderwijkse sisters: Bianca, Stella and Patricia Maessen. They worked in the late 1960s as session singers for, among other things, Dusty Springfield, until 1968, when they were discovered. In 1969, they recorded their debut album. In 1970, they sung "Waterman" (written by Pieter Goemans) as the Netherlands entry to the Eurovision song contest. They finished 7th out of 12 participants. The Eurovision experience did not further their career as expected.