The Independent, which live blogged the experience of reading the book, got early access to it ahead of its release this week. And it is precisely as strange, as shocking and as significant as the news about it shows – as you can see from the extracts collected below.

It is a wide-ranging book that concentrates on everything from Mr Comey's childhood to his spectacular firing – and, potentially, beyond. But much of the focus has been on what he says about Donald Trump, and the insights he gives into the man at his most tense and shocked.

He describes, for instance, the mood after Donald Trump heard about the now-famous spy dossier and its claims about a "pee tape"; he gives an insight into the strange video in which the president appears to kiss the then FBI director; he gives a peek into what it is like to go for private dinner with the president. They are, for the most part, excruciating.

Here are the highlights of all those experiences, and what they told us about the two foes.

1. James Comey still thinks he was right

This book is intended to be a vindication. It's obvious from the very beginning, right through to the end.

Mr Comey is astute enough to know that not everyone will agree with the things he did. But what he is keen on is proving that all of his decisions were made for good reasons, even if they had bad consequences.

This much might be true. But it is hard to see what use that it is to anyone who is not James Comey; bad decisions made well look the same as good decisions made badly from the outside.

2. James Comey is a very awkward man

Mr Comey writes at length about two hugs. And his formative moments with Donald Trump are largely spent avoiding him: he writes, for instance, of the excruciating pain that an invitation to a private dinner with the president caused him.

One gets the sense that it is not just the potential conflict of interest this presents – but also the fact that he will have to make small talk. In fact, he writes at length about how bad a conversationalist Mr Trump is, but fails to say exactly what he said to the president, and one gets the sense that the answer is not much.

At one point, for instance, Mr Comey describes the awkward situation after the inauguration at which he was in a room with the president. He is incredibly grateful that he managed to wear a blue suit and stand next to a blue curtain: "I literally clung to the blue curtain, all in the hope that I could avoid an ill-advised and totally awkward televised hug from the new president of the United States".

This is at least the second mention of being hugged. The first describes an interaction with then attorney general Loretta Lynch.

"When our bodies came together, her face went into my solar plexus as she wrapped her arms around me. I reached down and press both forearms, also awkwardly, against her back."

This might feel like a slightly superficial observation. But Mr Comey simply doesn't write about any interactions with anyone else that don't exhibit this awkwardness. Even when he meets with then Director of National Intelligence Jim Clapper, who was his boss, he embarks on an awkward description of re-gifting a tie that had been given to him by his brother-in-law.

The cumulative effect is that it feels often that Mr Comey simply struggled to speak to the Trump administration, in the most simple sense. There were principled objections between them, no doubt, and Mr Comey describes them at length.

But perhaps the biggest distinction is that Mr Trump is a man who does not care even slightly about principles, only about practicalities; Mr Comey, as he appears in this book, is someone who allows his principles to ruin even the lightest small talk.

3. Things could have been very different

If he was just a little less awkward, just a little more savvy, or had someone who forced him to be those things, then the course of events could be entirely different. Mr Comey appears to have written this book to vindicate the world-shaking decisions he made – but it ends up making clear how easy it would have been for things to be otherwise.

When he accounts for why he made the announcement of Clinton's emails, for instance, one is left yelling at him to just make a decision, and to stop the abstracted arguments about ideals. The same is true when he discusses his decision not to announce Russian interference in the election.

One is left wishing he had made some kind of evil, calculated, partisan decision; instead, the whole thing was decided almost arbitrarily. At least then the bizarre world we are left in would be this way for a reason.

None of this is to say that Donald Trump would not have won if any of these delicately balanced events and choices had gone the other way. But even if he still had, the Trump presidency would be a very different thing.

4. We still know very little about Donald Trump

James Comey is not afraid of telling you the little details about the president. In fact, he's sometimes a little obsessed with them.

He describes him in one long passage that reads something like a police report. It is worth quoting at length, even if that might make you feel "mildly nauseous", to borrow Mr Comey's own phrase.

"He appeared shorter than he seemed on a debate stage with Hillary Clinton," he writes. "Otherwise, as I looked at the president-elect, I was struck that he looked exactly the same in person as on television, which surprised me because people most often look different in person. His suit jacket was open and his tie too long, as usual. His face appeared slightly orange, with bright white half-moons under his eyes where I assumed he placed small tanning goggles, and impressively coiffed, bright blond hair, which upon close inspection looked to be all his. I remember wondering how long it must take him in the morning to get that done. As he extended his hand, I made a mental note to check its size. It was smaller than mine, but did not seem unusually so."

But for all this insight – perhaps a little more insight into Mr Trump's body than anyone might actually like – we get little understand of what is inside the president's head. Mr Comey went for a private dinner with the president, but all he recalls is that he was self-obsessed; he saw him at some of his most desperate and shocked moments, including talking about the now famous and embarrassing spy dossier, but doesn't give any detail on how that affected Mr Trump and his fragile and powerful psyche.

All of that means that despite Mr Comey's discussion of his principles, and his imploring other people to act on them, it is hard to actually know anything about how the president might fall. It gives us no real insight into what he might do next.

This is one of the things this book has in common with Michael Wolff's Fire and Fury – the last book about Donald Trump to cause this kind of a stir. That book, too, was packed with often strange physical details about the president, but little insight into his head.

5. It is not the end of the Comey story

Most of the book proceeds as you would expect it to: from youth, to a fledgling career in law enforcement, through serving under Bush and Obama, and into the Trump presidency. Mr Comey recounts all of it in often excruciating detail.

But then you reach the end of the book, and something a little strange happens. It seems that Mr Comey is suggesting that something else is about to happen – to him, or to Donald Trump, or both.

It could be a presidential run for Mr Comey. It could be the expectation of the end of Mr Trump's time in the White House. (It could be both, with Mr Comey hoping to take up Mr Trump's vacant spot.)

The end of the book is the point at which Mr Comey lays into the president in the clearest and strongest terms. But part of it also sound like a pitch.

""I am writing in a time of great anxiety in my country," he writes, for instance. "I understand the anxiety, but also believe America is going to be fine. I choose to see opportunity as well as danger."

In another he seems to be justifying the writing of the book, and the events within it. But he could also be justifying some future bid for power.

"It is also wrong to stand idly by, or worse, to stay silent when you know better, while a president brazenly seeks to undermine public confidence in law enforcement institutions that were established to keep our leaders in check," he writes.

And finally he concludes with a message to the next president. What if, perhaps, he means himself?

"The next president, no matter the party will sure emphasise values – truth, integrity, respect, and tolerance – in ways an American leader hasn't needed to for more than forty years. The fire will make something good grow."

But the most interesting comments come at the very, very end of the book, in its epilogue. After all the usual thanks – in which he thanks "some people" who "cared enough to tell me the truth" and made him think "this book will be useful" – he explicitly suggests that something else is coming.

"Thank you for the joy and the journey, which isn't over yet," he concludes.

It's hard to see how any bid for the presidency would happen, given that both the Republican and the Democrat establishments are firmly against him. But, then, they said the same about Donald Trump.

The Independent

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