Part theatrical experiment, part marketing coup, the decision to exchange nightly the roles of Victor Frankenstein and the Creature between Jonny Lee Miller and Benedict Cumberbatch manages to expose both the frailties and the strengths of Nick Dear’s adaptation.

Jonny Lee Miller (The Creature) and Benedict Cumberbatch (Victor Frankenstein) in Frankenstein at the Olivier, National Theatre Photo: Catherine Ashmore

The idea came from the play’s director, multi Oscar-winner and former Royal Court Upstairs helmsman Danny Boyle. He saw the scientist and his creation as two halves of the same character. Having the actors inhabit these halves on consecutive nights allows them, theoretically, to explore the whole.

It certainly would be interesting to see how they develop over the course of the play. They are very different performances.

As the creature, Miller’s performance is mesmerising physically - his whole body a spastic creation quivering with the confusion of new life. Director of movement Toby Sedgwick has created something stunning. Miller brings a warmth and humour to the role that draws the audience closer, enhancing the tragedy.

While Miller is engrossing to watch, Cumberbatch creates the creature from the head down. This is Shelley’s story told lite and yet it still asks the necessary existential questions.

To that end, Cumberbatch delivers an authenticity that Miller’s somehow more comic creation fails to. There is real intelligence to the creature under Cumberbatch’s guidance - the philosophical questions are burning within. He is both monster and man, he feels alive and yet, with his knowledge of Milton, feels as though he is an abhorrence of God’s natural laws.

With Victor Frankenstein too, Cumberbatch convinces as the tortured genius driven by his own ego to defy God far more than Miller. Miller instead gives to Frankenstein the arrogance of the captain of the college rugby team, good looking, strong and clever, but thuggish, too, and lacking the intellect needed to wrestle with the deeper meaning of his work.

Yet while this philosophical undercurrent flows beneath the text, somehow Nick Dear’s script lacks the weight or depth to reach it - exposed particularly when Cumberbatch is the creature.

Told on Mark Tildesley’s sometimes stark stage and under Bruno Poet’s flashing canopy of lights - symbolising the danger and beauty of scientific endeavour - this adaptation is about the two central characters and nothing else. The story quickly becomes gossamer thin around them leaving the other insubstantial characters to float away.

This lifelessness occasionally finds its way into the central story. How unchallenging, after all, is the conceit that we are born good only to be turned evil by mankind’s wicked ways?

“What is love?” asks the creature at one point. And suddenly the spell is broken and the auditorium, the exit signs and the coughing patrons come crashing back in.