In 2022, when Céline Dion shared that she had been diagnosed with a rare incurable neurological disorder called stiff person syndrome (SPS), there was no guarantee that the 58-year-old would ever tour again. Her condition, which resulted in muscle spasms so strong that it left her with broken ribs, had made it impossible to perform, and in a 2024 documentary, I Am: Céline Dion, fans saw how the disease had constricted her once seemingly infallible voice. Through it all, though, Dion was resolute that she would one day return to the stage. “If I can’t run, I’ll walk. If I can’t walk, I’ll crawl,” she said in the film. “But I won’t stop.”

Related: ‘She’ll outdo herself’: Céline Dion fans camp out for glimpse of star before sold-out Paris comeback

Thankfully at the opening night of her sold out five-week residency in Paris, her first full-length concerts in six years, no crawling is needed: Céline Dion is back. She glides on to the stage in a black dress, an enormous diamond necklace clasped around her throat, and launches into On ne change pas. There are tears almost immediately: she struggles through the second verse, her voice cracking as she begins to cry. By the time the strum of Destin has kicked in, though, that emotion is replaced with sheer elation. “I made a promise to be back on stage. Singing for you. Singing for me,” she says. “Singing for life.”

That she does. There is no cure for SPS, but the work Dion has put into managing her condition so she can perform again is astounding. Still, clearly some necessary allowances have been made. Some songs such as Because You Loved Me, The Power of Love and My Heart Will Go On have all been transposed down. It’s understandable given the effect her condition has had on her voice, although, in the case of Because You Loved Me and It’s All Coming Back To Me Now, it does somewhat dampen their melodramatic potency.

That is not to say that Dion’s voice is weakened: when she needs to, as she does on the driving Tout l’or des hommes, she can still belt out a note. There’s also some welcome texture to her vocal, too: recently released ballad Dansons sees her embracing her lower register, while Courage, recorded following the death of her late husband René Angélil, is genuinely affecting as Dion allows her voice to get fragile and raspy.

For some, Dion’s success – she has sold more than 200m records and is the third most successful female artist of all time – is inexplicable: to them, her music is the apotheosis of saccharin and anodyne adult contemporary. But for the 30,000-plus in the crowd tonight, that contempt is decidedly absent. After all, you don’t attend a Céline Dion show expecting anything avant garde. You’re there to hear Beauty and the Beast, an unexpected highlight.

Still, Dion does have some surprises up her sleeve: the run of J’irai où tu iras, Ne bouge pas and Dans un autre monde provides some rollicking respite from the balladry, Dion strutting up and down the stage while doing vocal acrobatics or fake boxing with backing singer. This is followed by an outlandishly camp disco section, complete with covers of Donna Summer’s I Feel Love (oddly enough, Moroder’s sequenced synths really are a great match), Sweet Dreams (Are Made of This) and a chandelier that quickly morphs into a glitter ball. As Dion shimmies about, separating the covers with a souped-up electronic take on That’s The Way It Is, a sly smile reveals that she, too, knows how ridiculous it all is.

Most astonishing, though, is a rendition of Ebben? Ne andrò lontana from Alfredo Catalani’s opera La Wally: wearing a pink feathered coat and standing a protruding rock that has just emerged from below the stage, Dion pays homage to Maria Callas as fake snow falls from the ceiling on to the audience below. It is brilliant and ludicrous and purists will loathe it. Nevertheless, the kookiness all feels very Céline.

Related: Big hits, massive ballads and titanic emotions: Céline Dion’s greatest songs – ranked!

The biggest response from the crowd, many of whom have likely been out practising at one of the many mass karaoke events celebrating Dion’s music throughout Paris this week, arrives during Pour que tu m’aimes encore. The singing is so loud it almost drowns Dion out. It is All By Myself, however, that seems like the most significant for Dion. As the piano solo and slide guitar gives way, she glances upwards before unleashing herself on that final chorus. When she realises she hit the big notes, it’s relief – then triumph – that spreads across her face. Given where she has come from, and her performance on stage tonight, it’s a feeling that is clearly well deserved.