FELA! is a bouncy, buoyant, corker of production that rather loses its way halfway through. The first half is an utter joy. Bill T Jones’ choreography does not flag for a second, the music is infectiously upbeat, the energy of the performers is relentless. It rattles along, full of exuberant lessons about Afro-beat, Cuban drumming, James Brown and high-life music.

The dancing, and the dancers, are utterly, superlatively, mesmerising. They are also universally stunning. Early on in his engaging narrative, Fela (Sehr Ngaujah) tells the audience that the British stole Nigeria’s oil and diamonds, and what did we leave in return? Gonorrhoea and Jesus. Doesn’t seem like a fair swap. This is indicative of the wit, warmth and brilliance that Ngaujah brings to the stage, making Jim Lewis and Bill T Jones’ words and Jones’ choreography zing and zip.

The whole first half was bursting with joy, life and gyrating buttocks. I don’t suppose that Sadler’s Wells has seen hundreds of people getting in touch with their “clocks” before: thrust your pelvis forward, that’s 12 o’clock. Now stick your bum out, that’s 6. Hips side-to-side hits 3 and 9. Now imagine a semi-naked, sinfully sexy man, glistening with sweat, getting the whole of Sadler’s on its feet, thrusting and foot-tapping as he shouts out numbers. Now imagine trying to follow his instructions while watching far more attractive, scantily-clad and adept dancers do the same moves on stage. In tassled knickers, and not a lot else. It made a refreshing change from pointe shoes and pirouettes.

With such virtuosic dancing and superb choreography, if it ended at the interval I’d say you’d be hard-pressed to have a better time in the theatre this year. However, after a well-directed come-down early in the second half, the show rather lost its way. It’s tricky to bring the mood down without alienating a happy, buzzy audience, but the story demanded it. The first hint of a sombre mood was a refreshing change, and was handled adroitly. However, the odd juxtaposition of joyful dancing and singing of the first half with stark, brutal and uncompromising descriptions of rape and torture in the second became rather baffling, especially when there were still song-and-dance routines mixed in.

A completely weird, massively over-long dream sequence that overestimated the dramatic potential of UV lighting took up much of the second half, followed by a beautiful but jarring operatic song (sung by the brilliant Melanie Marshall). It all sat very oddly with high-life rhythms of the first half and general feel of the rest of the piece. The musicians deserve a review of their own – we got a full blown gig along with the dance and a (mini) play.

It’s nice to see Sadler’s embracing something different, and a superlatively good cast kept the evening afloat as the play floundered. It’s worth seeing for the supremely talented cast and fantastic first half – but if you left at the interval you wouldn’t miss much.