I have half an hour to buy coffee, a croissant, the Spectator and think about flowers for Myrtle. No, that would be overdoing it, in addition to the radio gadget; anyway, she has already smelt a rat. The train is stationary at platform four. My suitcase has been stowed in the rack above my seat. Good old Woodward, never lets me down.

The first sip of coffee is so hot it brings tears to my eyes. I remove my specs and dab away with a white handkerchief, checking an imaginary emotional pulse to see if I feel grief. Nothing yet, too much else on my mind.

Several options need to be sifted. Accident, or suicide? Certainly no accident. The apparent speed of descent suggests a predetermined act. Also, the van slewed off at the only unfenced stretch on the whole riverbank. Presumably the driver was aiming for it.

Suicide, then. Couldn’t face public exposure, one way or other. Saw no way out. Maybe left a note? We’ll know soon enough.

But suicide is a capital crime in the Torah, equivalent to murder. Dovidl would have had to renounce his faith before charging into the depths. Did belief mean so little to him? And why now? He had weeks to spare, time to put his affairs in order before I came to drag him into the limelight. Dovidl is not an impulsive man; he is never pressed for time. Keep this option open, I warn myself. There is more here than meets the average intelligence.

Murder? Faint possibility that some racist lunatic rode him off the road, shouting, ‘Ingerland, Ingerland,’ as the bearded Jew went into the river, flailing behind his rolled-up window. Can’t be ruled out, but there are not many drunken bigots about at six o’clock on a February morning. And what was Dovidl doing out so early, when he did not need to be at morning prayers until seven thirty?

How did the rabbis and their disciples come to be swaying on the bridge so soon after the ‘accident’? They were chanting in the background on the BBC news report, at seven twenty-six when they would otherwise have been on their way to morning prayers. They should have been unaware of Dovidl’s absence until he failed to show up for devotions, certainly not before eight. There may be a red herring here, and it’s starting to stink.

What about his wife? Had she rolled over in bed after six, found her husband missing and called out a search party? Surely not. Married couples in the ultra-orthodox community do not share beds. They sleep in twin singles, separated by a bedside table, to keep them apart during times of impurity. So the chance that Mrs Katzenberg missed him and raised the alarm is remote.