Hearts of Soul was formed by three Dutch Indo sisters from Harderwijk: Bianca, Stella (born 1953) and Patricia Maessen (1952–1996). They later moved to Veghel, also in the Netherlands.
They worked in the late 1960s as session singers for Dusty Springfield until 1968. In 1969, they recorded their debut album. In 1970, they sang Waterman (written by Pieter Goemans) as the Netherlands entry to the Eurovision Song Contest. They finished 7th out of 12 participants. Their single "It's Great Fun" was arguably their most popular at the time. They collaborated in 1972 on a single with Marius Monkau. The song "Oh Complete Jesus" is still popular, especially among religious people.
In the mid-1970s the group moved to Belgium. There they formed Dream Express in 1975 with former Pebbles musician Luc Smets (who married Bianca). In the summer of 1976 they had a Flemish number 2 hit with the self-titled song "Dream Express". On 5 February 1977 they won the national finals in Belgium to enter the Eurovision Song Contest 1977, which was held in Wembley, London on Saturday 7 May. This was the first time that Belgium had entered a song to be sung entirely in English. With the song "A Million in One, Two, Three" they reached 7th place out of 18 participating countries.
Dream Express changed names again in 1979 to LBS, which stood for Luc Bianca Stella. Their singles LBS and Uncle Jim received much airplay in 1979.
Stella also released singles under the name of Stella Mason. She represented Belgium (singing in French) in the Eurovision Song Contest 1982, with the song "Si tu aimes ma musique". On 24 April 1982 she finished 4th.
Bianca released several singles from the early 1980s through to 1993. The single "Two Dolphins to the Range of Hawaii" was released as a tribute to the 100th anniversary of the creation of the Antwerp zoo.