Rocío Molina has completely redefined what flamenco can be. Some purists say she’s not flamenco at all, and when, three quarters of the way through her latest piece, Calentamiento, she sits down at a drum kit and starts bashing out a 4/4 rock beat, maybe you would agree with them. But however crazy things get two hours in, everything is built on the pure craft of the flamenco dancer, and that’s where we start in this piece on the subject of beginnings.

Calentamiento means warming up, which is what Molina is doing on stage before the audience has even sat down. She begins a footwork drill, a 12-beat phrase, the same one she has done since she was seven years old, she tells us. At 140bpm, she likes to start slowly (!), she says. Heels and toes hammer out the dancer’s daily ritual, the same way even the most prima of ballerinas starts each day back at the barre with a plié; the constant discipline of beginning again.

There are lots of questions and lessons for life here. Why do we keep starting over? How do we keep going? She must keep beginning so that it never ends, says Molina, while her beats spark like a series of electric shocks. The “warm-up”, the whole first hour of her show, lays out her genius. Some of Molina’s recent work has tended towards the opaque, but working with writer/director Pablo Messiez, she makes direct connection with the audience, reveals her rituals, asks for a cigarette, chats to us as she ups the tempo to 180bpm, “getting acquainted with the pain”, she says, relishing pushing through that barrier.

She is a brilliant technician and she dances with absolute decisiveness, every pose of her body distinct and distinctive. It all comes from a powerful centre, a steel core – when you feel your balance going, she says, hold your arm out as if stopping a bus: the mundane, the comic, the sublime, all in one moment. At this point there’s only the sound of her feet, and the way she uses rhythm, tone and colour is a kind of storytelling in itself. Molina makes shapes with her body no other dancer does. In one sequence it looks like choreographer Jiří Kylián doing flamenco.

“To dance I need to be sweaty and tired,” Molina says. But there’s nothing tired about what she does. Once Molina gets into the “show” part of the show, Calentamiento goes off in wild directions, five singers appear in a neon box making silly noises (as well as highly skilful ones); there are transformations, drama, satire, a pile of metal chairs, some thumping bass. She says she wants a show that never ends – this one is two hours, no interval, but you stay with her. It’s thrilling, curious, surprising, witty and always stunning to watch her dance (punk spirit, precision craft). That drive to keep moving in the face of it all may be a massive metaphor for life, but it’s also a very particular, personal portrait of what it is to be a dancer.

• The Flamenco festival is at Sadler’s Wells, London, until 29 June