With his wild locks and impish grin, Steven Isserlis always came across as a perennial infant, until his magisterial recordings of Bach's Cello Suites revealed the wisdom of a sage. Yet here he is, celebrating his 50th, so he's still a relative child after all. Sweet that he doesn't hog the stage: that's for the musicians with whom he's played such distinguished chamber music over the years.
First at the piano is the house manager, who leads us all in "Happy Birthday to You", after which the fun begins. Andras Schiff announces that while Isserlis's birthday is actually later in the week, Beethoven's is today, whereupon he plays the shortest Bagatelle Beethoven ever wrote, all 13 seconds of it – twice, so we get the point. But his main business is Bach's Italian Concerto, which he delivers with such force that the Steinway sounds positively plummy.
Next up are tenor Mark Padmore and soprano Dame Felicity Lott, to sing two Haydn songs. These lean on piano writing as deep as that of his late sonatas, but Schiff is a slightly unyielding accompanist. Then they sing some Dvorak, after which the bearded and grizzled Radu Lupu walks on like an ancient holy man. He leans back, closes his eyes, stretches out his arms, and Schumann's Arabeske in C flows out as though of its own volition. Then Schumann's Kinderszenen plays itself, with Lupu deep in a dream. It's wonderfully singing and idiosyncratic, and we follow where the fantasy leads. The instrument now seems quite different from the one Schiff has just played: this is the magic that has made Lupu a legend. How does he do it? God alone knows.
What's fascinating is to see how he's revered by the other musicians: Schiff sneaks back in to listen from behind a potted plant.
After the interval, Joshua Bell, accompanied by the pianist Jeremy Denk, delivers Janacek's mercurial Violin Sonata – Bell at his perfect best – before Padmore and Lott return with some Fauré. Then comes something extraordinary: Schiff and Lupu, who have never duetted in public before, give us Schubert's sublime Fantaisie in F minor.
How will head (Schiff) and heart (Lupu) meld? Since Lupu takes the singing upper part, the answer is, magnificently. After a bear-hug from Lupu, Schiff changes places with him for an encore: a calmer, more equable piece, in the playing of which Lupu's benign spirit seems to have entered his soul too.