Speaking on Halloween, the Prime Minister announced a second national lockdown, directing the public to stay at home unless for specific reasons, such as attending school or college, or going to the supermarket from 5 November.
But when exactly did 'Lockdown 2.0’ start, and when does it end? Could it be extended even further?
Here is everything you need to know.
When does lockdown 2.0 begin?
England's second national lockdown began at 12.01am on Thursday 5 November.
The reason it was not imposed immediately, as it was back in March, was to give MPs a chance to vote on the new measures.
They did this on Wednesday 4 November, and the changes were approved by Parliament, despite a small revolt among Tory MPs who were against a second national lockdown.
Labour leader Sir Keir Starmer said his party would vote in favour of the latest coronavirus restrictions but warned of the “cost to that delay” in locking down.
He told BBC One’s Andrew Marr Show that "the lockdown now will be longer, it’ll be harder, we’ve just missed half-term and there’s a very human cost to this.”
When does the second lockdown end?
England's second national lockdown will end at 12.01am on Wednesday 2 December.
After that date, the Government will reintroduce local restrictions based on the latest data and trends.
The four-week length of the lockdown was set out by Boris Johnson, and means that this time around there is a very definite end.
During the first lockdown, the government reviewed measures roughly once every three weeks.
Could the lockdown be extended?
The end date is set in law, though in theory the lockdown could be extended if it deemed entirely necessary – though it again would have to go to a vote in the Commons.
Earlier in the month, Cabinet Office minister Michael Gove admitted the lockdown could last longer than an initial four weeks and extend well into December, if the R value – the average number of people infected by one infectious person – does not drop.
“We want to be in a position where we can – and I believe that this is likely to be the case – have an approach where if we bring down the rate of infection sufficiently we can reduce measures nationally and also reduce measures regionally,” Mr Gove told Sky News.
Asked whether the national lockdown could be extended, he replied: “Yes.”
What happens after this lockdown?
The Government has since been clear that the lockdown will end at its originally proposed time, and has announced a plan for tackling the virus going forward.
It means the return to the three tier system of local restrictions that England was under before the second lockdown, and the measures included in each of the three tiers have been tweaked to be more stringent.
An announcement on which areas will fall into which tiers is expected on 26 November.