Perhaps he thought he'd suddenly been transported to his own rehearsal room and had to speak up and give notes. Whatever was going on, you felt for him. As you do when someone has an incontrollable coughing fit, as I very nearly did in the first act. A kind person in the row behind tapped me on the shoulder with a bottle of water. At least I wasn't checking my phone messages or tweeting.
There was a commendable reluctance on anyone's part to identify Hall as the phantom heckler, but the tweet gates soon opened over the weekend and Viv Groskop spilled the beans. Tim Walker of the Telegraph then filed a rather gloating story online, suggesting that the critics were being a bit coy about not identifying Sir Peter in all this, though it was hard to be sure about the source of the disruption unless you were sitting on the left hand side of the stalls towards the front. But Hall did rise and exit smartly with his wife, Lady Nicki, before the curtain calls.
After oddly dissociating himself from "the critics," Walker - who is a critic himself on the Sunday Telegraph, as well as a diarist on its sister title, the Daily Telegraph - then muddled the play's plot lines, stating that Sonya (Laura Carmichael's role) was Vanya's brother and the professor their (as opposed to her) father.
That error was corrrected in due course, and the kerfuffle in general seemed to subside in a welter of smoothing over and apology, Hall even issuing a statement to the effect that he thought the show was marvellous and the actors superb, and distraught theatre owner Nica Burns going out of her way not to be critical of Sir Peter, whom she reveres as a friend, colleague and theatrical colossus. My own view, as I say in my review, is that these things happen: it's live theatre, baby, and all part of the fun.
Paul Freeman, who plays the professor, was certainly sanguine about the incident at yesterday afternoon's tea party thrown by The Theatrical Guild in the Elgar Room at the top of the Albert Hall. "Mind you," he added ruefully, "I was lucky in not being on stage at the time."
The Theatre Guild, now known as the TTG, was once the Theatrical Ladies' Guild, and their tea parties at the Albert Hall were a regular feature of the theatrical calendar over a century ago, with songs, recitals and themed tables hosted by the great names of the day, such as Irene Vanbrugh, Marie Tempest and Marie Lohr.
The charity's main business hasn't changed, even though there are far fewer big hats and less tea dancing: it raises money from stunts, raffles, donations and appeals in order to help out indigent, or even just retired, backstage and front of house staff. Today, its president is Phyllida Law, its chairman Jane How, its patrons Simon Russell Beale and Keira Knightley and its prominent supporters include Benedict Cumberbatch - and Peter Hall.
So a fine, representative cross section of the theatre industry sat down at tables to enjoy sandwiches and scones, tea and champagne, followed by a cabaret performed by Issy van Randwyck and Kit Hesketh-Harvey, no longer one half of Kit and the Widow, alas, as he and pianist Richard Sissons, the Widow, have gone their separate ways after a bust-up over the writing of rival books.
Issy's turn was an unusual mixture of the insalubrious and the coy, falling hilariously all over the place in a "drunken" stupor before singing about how she always talks to flowers ("Hiya, Cinth") and indeed "Tulips from Amsterdam" - which she sang in Dutch, and in a pair of very bright yellow, noisy clogs.
Kit, accompanied nowadays by James McConnell, has re-mastered Abba's "Fernando" as a mock tribute for Nando's chicken restaurant chain, complete with camp tango poses, and does a wonderful satirical setting of Chopin's lushest piano music as a lament for the missing plumbers in Poland - "they are all in Willesden Green."
And he ended with a community singalong deriding Silvio Berlusconi to the tune of "O Sole Mio," complete with song sheet. It put us all in a splendid pantomime mood, and reminded us that theatre is all about joining in, which is perhaps the point Peter Hall himself was trying to make on Friday night.
Anyway, the Albert Hall galaxy included Liz Robertson and her (very) grown-up daughter, Rosalind Knight, Tilly Tremayne, Giles Havergal, top agent Barry Burnett (and his mother came, too), Freddie Fox (and his mother, Joanna David, came as well), Patrick Marley, publisher Marcus Clapham and Sheila Reid.
My immediate neighbours at table were Trevor Peacock and his son Harry - and Harry's wife, the brilliant comedy actress Katherine Parkinson, last seen on the West End stage in Absent Friends at the Harold Pinter. She was pregnant during that run and brought along the end result, three-month old Dora, who behaved impeccably during the tea and the cabaret, just like any becalmed West End first-nighter.