Mezzo Soprano was a dark bay or brown mare with an elongated white star bred in Kentucky by her owner Sheikh Mohammed's Darley Stud.
Ridden by Olivier Peslier she took the lead 200 metres from the finish and won "easily" by a length from State of Art, a filly who went on to win the Prix de la Nonette.
[7] On her return to Europe Mezzo Soprano went off the 7/1 fourth choice in the betting for the 1000 Guineas on 4 May over the Rowley Mile at Newmarket Racecourse but after racing prominently she dropped away in the closing stages and came home fourteenth of the nineteen runners behind Russian Rhythm.
At Royal Ascot on 19 June she was moved up in distance to contest the Ribblesdale Stakes over one and a half miles and briefly took the lead in the straight before being overtaken and coming home third behind Spanish Sun and Ocean Silk.
Twelve days later the filly was ridden by Frankie Dettori in the Listed Galtres Stakes over one and a half miles at York Racecourse and started the 4/1 joint favourite alongside the Henry Cecil-trained Singleton.
[10] For her final race, Mezzo Soprano was sent to California for the Breeders' Cup Filly & Mare Turf at Santa Anita Racecourse on 25 October where she made little impact and came home unplaced behind Islington.