A 30-strong crew of Mensa's friends rush the stage, leaping up and down till the fixtures groan.
Soon enough the traditional Wolof rhythms, anchored by the percussionist Babacar Faye and the hand drummer Assane Thiam, took over and sent Mr. N'Dour tumbling around the stage, leaping into a sensational falsetto and back to his normal tone, a leader of a frenetic group dance.
Whatever the answer, some guy called Ben Thomas has been made to stand behind the decks while the nine-headed maelstrom Odd Future Wolf Gang Kill Them All fling themselves around the stage, leaping off speaker stacks, fighting and barking out dank doom raps.
But he hits the stage like a jumping jack, Mick Jagger times David Lee Roth, divided by Steven Tyler: racing back and forth on the stage, leaping from risers and performing split kicks -- he's a human pinball, caroming around the stage.
Points are awarded for the following: finishing each stage; leaping over obstacles; destroying objects with a hammer power-up; collecting items such as hats, parasols, and purses (apparently belonging to Pauline); and completing other tasks.
Peter Mussbach's staging leaps neither forward nor backward in time but is busied by film projections and a few touches of the surreal.
As songs ended, she would collapse onto the stage, then leap up with a hand wriggling at her chest, miming a fast-beating heart.
Then, when they have worked themselves up into a frenzy of self-admiration, they sprint across the stage and leap into what they imagine is the loving arms of their adoring fans.
He's not helped by Richard Hudson's awkward design - two slanted wooden platforms converging to impenetrable purpose - or by some fussy directorial points: masked and gowned figures glower round the stage, and leap on to it when anything morally dire occurs; smoke belches; drums beat like the pulse of a heart at climactic moments.
The 2011 Tour winner looks in fine fettle, finishing second on the stage to leap to third in the general classification.
