Confused about her sexuality and seeking an escape from controlling parents, Jeannine Deckers decided to give everything up to become a nun - but that was just the beginning of her story.

If you’ve ever found yourself slumping into a sugar coma induced by Debbie Reynolds trilling gaily in The Singing Nun, you might be surprised to learn of the queer history and haunting tragedy behind the woman who once beat The Beatles to the top of the Billboard charts with global hit ‘Dominique’.

Starring the effervescent Cécile de France, Belgian writer/director Stijn Coninx’ 2009 biopic Sister Smile (Sœur Sourire), now available at SBS On Demand, offers a much more enlightening insight into why Jeannine Deckers, the woman who would become "The Singing Nun", ended her own life in such alarming misery.

Born in 1933, the daughter of a baker living in the suburbs of Brussels, music was a cherished escape for Deckers during a difficult childhood, writing her own songs and playing guitar.

Cecile de France (right) in Sister Smile.

Source: Ocean Films

Confused about her sexuality and seeking an escape from controlling parents, Deckers, in a strange fit of rebellion, decided to give everything up, entering the Missionary Dominican Sisters of Our Lady of Fichermont nunnery in Waterloo at the age of 25. Well, she didn’t quite give everything up.

Known as something of a rebel in the suffocatingly cloistered environment, in which the hot-headed Deckers struggled to play by the rules, she continued to play guitar, entertaining her fellow nuns, and then the local community, with her concerts. It was her salvation in such a repressive environment, resistant to her calls for social progression, but it would also prove her downfall.

Spotted by music executives from Philips Records, who could smell a profitable gimmick a mile off, they were successful in convincing a less than improving Mother Superior to let Deckers record with them in return for a steady stream of the profits.

Sister Luc Gabriel, as Deckers was then known, recorded the single ‘Dominique’ about the founder of her order, St Dominic, casually overlooking the fact he was the mastermind behind the brutal Spanish Inquisition, an omen of bad luck if ever there was one. Not for nothing is the irritating song on an eternal loop of damnation in Ryan Murphy and Brad Falchuk’s American Horror Story: Asylum.

Proving a massive success worldwide, including number one in Australia, the sickly sweet MGM movie followed three years later, though Deckers branded director Henry Koster’s tale largely “fiction”. Between this, her appearance on The Ed Sullivan Show and even a Grammy Award, Deckers suddenly found herself an unlikely megastar.

Recommended Sister Smile Review Repression and liberation collide in the troubled tale of the price of fame.

This newfound and short-lived fame was a heady brew, with a mixture of personal ambition and hubris finding her unpopular back at the convent, though jealously on the part of her fellow nuns may have played its part in her increasing unhappiness and bewilderment. In the meantime, ‘Dominique’ and Deckers’ debut album made a fortune for the record label, with her share going directly into the convent’s coffers.

Coninx’ Sister Smile, co-written by Ariane Fert and Chris Vander Stappen, charts this meteoric rise and the catastrophic collapse that followed. Frustrated by convent life, de France’s Deckers leaves it all behind once more, moving in with childhood friend Annie Pécher, 11 years her junior, played by Sandrine Blancke. Though Pécher quickly became infatuated with Deckers, the older woman remained true to her vow of chastity and ill at ease with her emerging sexuality for many years before the pair eventually became lovers. Blancke adeptly conveys a bristling sense of injustice at this resistance.

Attempting to resuscitate her musical career, first Deckers was barred from using her famous pseudonym by the convent and then abandoned by the recording company and several concert venues after she released a controversial song defending contraception, ‘Glory be to God for the Golden Pill’, which also had the unfortunate effect of large swathes of her remaining, deeply religious fans turning their backs.

Excessive drinking and a drug problem ensued, exacerbated by a huge bill for back taxes on royalties lodged by the Belgian government, despite the fact she had never seen a penny for her massively successful one-hit wonder. Facing destitution and possible imprisonment, tragically, Deckers and Pécher took their own lives in 1985.

If Coninx, who recalls having ‘Dominique’ stuck in his head as a six-year-old, puts a slightly soft spin on the finale, de France is a towering presence that honours a fascinatingly conflicted Deckers, far more complex than the sweet-natured nun portrayed by Reynolds, with the film all the better for it.

You can watch Sister Smile now at SBS On Demand: