Giacomo Casanova may not have been a tinker or a tailor, but he was briefly a soldier and certainly a spy, not to mention a trainee cleric, a diplomat, entrepreneur, musician, cabbalist and, of course, lover, too. That he was able to slip between so many roles is testimony not just to the times in which he lived — an 18th-century Europe in which professional identities had yet to settle.

For if Ian Kelly has one thing that he wants us to take away from this great onward rush of a biography, it is that Casanova remained as he had begun, a professional actor whose life’s work was the performance of his own mercurial self.

He was born poor and rackety in 1725, the probably illegitimate child of a Venetian stage comedienne. The fact that his mother had affairs with any important passerby, including the Prince of Wales, scarcely translated into viable social capital.

Instead, it was Casanova’s obvious cleverness and curiosity which got him an education that culminated in becoming a doctor of law at the age of just 16. His precocity showed in other ways, too. His first love affair, at 11, was a textbook seduction by the slightly older girl whose job it was to keep him clean. A bit of thigh-washing led to a delicious first climax and, almost as inevitably, into a complicated ménage involving his nursemaid’s official swain.

Thankfully none of this gets in the way of a good old-fashioned sex romp, which is why, after all, people keep on wanting to read and write about Casanova. Kelly is not too proud to give us what he knows we’re really after: naughty nuns, threesomes, virginity-taking, and lots of peeping through keyholes. Kelly organises his biography into Acts and Scenes. This struck me as slightly heavy-handed, although it does offer the chance for a really fine “Intermezzo” in which Kelly halts the action and talks directly to the audience about Casanova and travel, sex and, most interestingly, food.

Anyone who writes about Casanova is standing on a whole cohort of shoulders, so it is entirely to Kelly’s credit — specifically, his ability to reimagine life on the hoof in 18th-century Europe as a series of exhilarating mini-dramas — that he has managed to make this story feel so fresh again.