By William Gallagher BBC News Online

There is no joke in the title of Michael J Fox's autobiography, Lucky Man, but there is a lot of irony.

He claims - and you will believe him - that he would never want to go back to the man he was before he learned he had Parkinson's Disease.

But he says so with such bouncy, readable wit that when he talks of the frustration of the disease, at its peaks stopping him writing or articulating, it is desperately moving.

Fox is not maudlin once, though he comes close with some descriptions of his family, and is neither self-serving nor too self-deprecating.

Fox's drinking nearly broke up his marriage

He does perform in the book, judging just when to hit you with a gag - "Having Parkinson's at an auction can be an expensive proposition".

But overall the sense is of someone very smart, and quick being as straight with you as if you were an old friend catching up with him.

Fox also happens to be the star of sitcoms Family Ties and Spin City, plus films such as Back to the Future and so many more.

So if he speaks of location filming or famous co-stars, it is to tell you about them, not to make you starry-eyed.

Secret

"I can vividly remember all those nights when the studio audience, unknowingly, had to wait for my symptoms to subside," he says of his hit sitcom Spin City.

"If a studio audience were to detect a tremoring of my arm, a slowing of my speech...it would... be decidedly unfunny."

Like a novelist, he tells you what it was like to hide the disease only partly to convey the moment, and much more to set you up for what it was like when he went public.

Fox has had a prolific film and TV career

"It would be disingenuous to suggest that I didn't expect some media attention...but in no way did I anticipate the magnitude of the reaction."

That is a charming but rare mis-step in his pragmatic assessment of himself and how he is perceived. Fox is surprisingly level-headed throughout the peaks of his career and troughs of the disease.

Admitting to an alcohol problem that he did not face up to until after his diagnosis, he is able to convey the depths of drink-sodden misery he reached.

But he knows enough to add: "I'm sure many people reading this now are thinking, "'I spilled more than you drank'".

Humour

It is hard sometimes to follow the chronology of the drinking episodes, and quite when some events happened. Fox zips around his life drawing parallels, telling funny asides that later prove important to the tale.

What you come to realise is that this is an autobiography with a mission. Fox does not want to tell you his life story for no reason, he wants to convey the massive impact of Parkinson's on someone.

It is an eloquent, tremendously well-written jaunt which, if it paints Michael J Fox as a thoroughly good bloke, does so convincingly.

Lucky Man: A Memoir by Michael J Fox is published by Ebury Press. From April 22 to 26 Fox reads an abridged version on BBC Radio 4