Being in the throes of what Sophie Ellis-Bextor calls a "mid-pop-career crisis" can make for interesting outcomes. The singer's crisis was brought on by her feeling pigeonholed as a posh dance act, and making some what-was-I-thinking decisions along the way (it's said that Kylie only recorded Can't Get You Out of My Head because Ellis-Bextor had turned it down). Breaking away from the image led to an appearance on Strictly Come Dancing and, perhaps more lastingly, a musical reinvention. If she pulls it off, Ellis-Bextor Mk II will go down in pop history as one of the great unlikely turnarounds.

Tonight's show is the first performance of her new album, Wanderlust, a collection inspired by multiple tours of Russia, where she's a rather improbable superstar. Anglicising the drama of traditional eastern-European balladry, she and co-writer/producer Ed Harcourt (who's tucked away at the side of the stage tonight, playing keyboards) have made a singer-songwriter album with a melancholy Balkan heart. She plays it in full here, from the florid Birth of an Empire to 13 Little Dolls, a gypsy fiddle breakdown with "Eurovision 1975" all over it.

"There are things you can't talk about or sing about in dance music," she says, by way of apology to anyone expecting a setful of glitter-ball hits like Murder on the Dancefloor. Her disco era, including Groovejet (If This Ain't Love) and a silky cover of Moloko's Sing It Back, is represented in the encore, but the meat of the show is given over to Wanderlust – and it comes with a sartorial change of image, too: her longsleeved, high-necked dress is a figurative kiss-off to the disco chicklets who show acres of skin.

Can it work? She certainly puts her all into these dramatic songs, and the album is currently No 4 in the iTunes chart. Remodelling herself could be the best thing Ellis-Bextor has done in years.

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