Did you ever have that panic-inducing dream? Maybe you've had the "taking the final exam in a course I've never attended" nightmare. If so, the look on your sleeping face was probably like the one on pianist Maria Joao Pires in this video, when she realized she had showed up for a concert with the Royal Concertgebouw Orchestra after preparing the wrong concerto.
This moment of confusion came before a free rehearsal for the evening performance, but the hall was full of people. (The Charlotte Symphony invites the public to its rehearsals, too.) Pires had the right composer: Mozart, one of the three men this poet of the keyboard has made her specialty all her career. (The others are Chopin and Schubert.) But where music director Riccardo Chailly had prepped his orchestra for Concerto No. 20, Mozart's most dramatic, she had been working on the sunnier 21st.