William would become king, but then things get weird. I strongly suspect there’d be a rushed act of parliament on behalf of the dead Charles, to whom the parliament was loyal, in order to - ahem - reign in this inexplicably power-mad William and perhaps even try to seek to apply some kind of punishment.

I could see a cross-party vote to not recognise William as king because of the grievous act and instead choose to recognise the next in line who was not in favour of that grievous act. This might mean that parliament chooses to recognise George as king and seek to appoint a regent in his stead until he was of age, for example.

Whatever was to happen I don’t think there’d be a civil war over it, but there’d probably be a referendum on becoming a republic fairly soon afterwards so the whole thing could be sidestepped.

If it turned out William wasn’t acting alone then I still think there’d be an investigation as to who was in favour and maybe expunge William’s line from succession altogether… but then I don’t think the powers that be would want Harry as king either. Or Andrew.

Edward would be unwilling, but I think he’d make a good, if quiet, king.

Anne would be f**king hilarious.

But all of this is moot. The chance of Wills becoming a homicidal maniac is about as likely as his gran coming back from the grave and doing the job herself.