On 7 November 1974 Sandra Rivett, 29, was bludgeoned to death in the basement of a house at 46 Lower Belgrave Street, London. A second woman, Veronica, Countess of Lucan, was also attacked and she survived to name her estranged husband, Richard John Bingham, 7th Earl of Lucan, as the man who assaulted her.

He would, in his absence, be named in court as perpetrator of both of these crimes, but he would never be tried. Because the last confirmed sighting of Lord Lucan was in the early hours of the following morning.

The case was – and continues to be – a cause celebre, because there have been sightings, and suggestions that wealthy friends had helped him to escape and start a new life abroad.

Much attention has been given to Lord Lucan’s possible fate , but little attention has been given to the questions of what really happened that night and of whether or no it was fully and properly investigated. Laura Thompson addresses those questions in this book.

It’s lucky that I’d read her work before – I loved her biography of Agatha Christie. Had I not I might not have made it through a rather lengthy introduction that could have made its key points – that there had been domestic murders, that there had been aristocratic murderers, but never before had an aristocrat been accused of a domestic murder – far more effectively in just a few pages.

In the body of the book she displays a much surer touch, and it is clear that she has done a fine researching all of the background and the facts of the case. She evaluates the origins of a tragedy, she reconstructs events on that terrible night and she considers the consequences, for the Lucans, for their families and for their friends.

I was fascinated by characters of Lord and Lady Lucan. Both had insecurities rooted in childhood experiences; she had become an insecure, and maybe emotionally unbalanced adult, and she had suffered badly from post-natal depression after the births of her three children; he had a destructive addiction to gambling. It was easy to see that despair at his failed marriage, his loss of the custody of the children he adored, and his spiralling gambling debts might have left him in a position which he considered only desperate action could resolve.

But there are conflicting facts, there are gaps in the evidence, there were prejudices, and some things are not quite as straightforward as they appear to be in the story presented to the world.

There was a lot to consider and a great deal to talk about. I looked up from my book to ask, ‘did you know …’ quite a few times.

I was astonished that a magistrates courts could pronounce someone a murderer without any defence being presented – and that practice wasn’t outlawed until 1977.

I was struck that Lady Lucan was the only witness and that, after being attacked in the dark, it was possible that she drew the wrong conclusions. She has had to live with the consequences of that night for more than forty years now.

I was pleased that proper consideration was given to the story and character of Sandra Rivett, and to question of whether she might have been the intended victim of the murderer rather than a victim of mistaken identity.

I was disappointed – though not entirely surprised – that there was no thorough investigation, that the police accepted Lady Lucan’s account of events and that evidence was lost while they pursued her missing husband.

Laura Thompson is very strong on social history and on building – and deconstructing timelines and scenarios. It is clear that she is intrigued by her subject. But I have to say that as whole the book might have been edited a little to make things a little clearer and to allow consideration of each chapter considering a different aspect of the story to be more complete in itself.

I’m still a little confused about who was who in Lord Lucan’s social circle, but I understood enough to follow the sequence of events and to understand and evaluate the arguments put forward.

She considers a number of alternatives scenarios, settling finally on one where Lucan hired a hitman to kill his wife and then intervened, either because he changed his mind or because he realised that something had – or might – go wrong. I’m inclined to agree.

She dismisses the possibility that he was helped to escape, and the so called conspiracy of silence of his gambling friends. And her argument that he died by his own hand, not wanting his beloved children to see him tried, not wanting to live with the consequences of events he had set in motions, not believing that he could turn his life around is compelling.

The analysis is fascinating, the questions that will never be answered are intriguing, what has stayed with me is the human story of those who were caught up in events that November night, and this who have – and who still are – living with the consequences.