When was the last time you went to the theatre? And before that? If the answer to both questions is within a month or two before coronavirus closed playhouses on March 17 then you were part of a demographic once known as the theatregoer.

For this group congregating was one of two main reasons to go to the theatre. The other was the live nature of the performance. But now the once understandably marginal interest of viewing recorded plays online is becoming mainstream as theatre is piped into the homes of a population under lockdown.

At the time of writing, there were 732,488 views of Danny Boyle’s 2011 National Theatre production of Frankenstein in which Jonny Lee Miller and Benedict Cumberbatch swap the roles of creator and creature.

Latest is Simon Godwin’s 2018 production of Antony & Cleopatra with Ralph Fiennes and Sophie Okonedo. Even streamed on to a computer screen the latter’s performance fulfils all the promise that old-school theatregoers saw when, as a little-known north London Jewish actor, Okonedo made her National Theatre debut playing Cressida 21 years ago on the same stage.

To this growing list of online works the Donmar Theatre’s Michael Longhurst has redirected Adam Brace’s 2011 work Midnight Your Time.

When it premiered, the one-woman-play was an early attempt to explore isolation in the digital age. This revival sees Diana Quick revisiting the role of an Islington lawyer who communicates with her daughter. This time, the play has an extra edge because Quick returns to the role in front of her web-cam at home, much like her character. But the edge of being a live performance is absent.

Also being made available is Opera North’s production of Leonard Bernstein’s Trouble in Tahiti. Fair enough. Some works will never lend themselves to social distancing. Bernstein’s score would sound distinctly muted with the brass and woodwind sections of the orchestra wearing masks.

The 50-minute opera about American life in the 1950s based on Bernstein’s own family will be made available until June. This takes us beyond the date the current restrictions to theatre were scheduled to last. But no one believes the doors will open thereafter. As West End producer Cameron Mackintosh pointed out this week, theatres could be closed until next year.

The West End and Broadway “are going to be the last to go back,” he said. This leaves theatremakers with a conundrum that isn’t going away anytime soon. With all this online theatrical material how do you preserve the quality that makes theatre distinct – its ephemerality? The question was first posed when, under Nick Hytner, the National Theatre pioneered NT Live which made National Theatre performances (followed by all kinds of theatre) available in cinemas all over the world.

But “live” in that context has not always meant audiences watching a performance that is simultaneously happening in the flesh somewhere else. Often it just means recorded live.

So as lockdown theatre is set to continue into the foreseeable, one of the key challenges for the likes of the National Theatre’s current director Rufus Norris, and other guardians of theatre, must surely be to find ways in which performances that are digitally streamed into our homes are genuinely, theatrically live.

There are attempts to do this, among them Headlong’s forthcoming Unprecedented season which will feature short new plays written and performed by top theatre talent. And, in America earlier this week, New York’s The Public Theatre enabled a web broadcast of a new work written for the lockdown era by playwright Richard Nelson.

We need more of this. Theatre needs more of this. Because no matter how great a production was when it was filmed, if a play is not live, if a performer is not living a part of their life with the audience and vice versa, an essential part of theatre is dead.