Whatever else, Bebel Gilberto is brave. She started her show by lying provocatively on a couch in a red dress, as she launched into Momento, the first of many breathy ballads. It looked as if she was suffering from a serious overdose of bad taste until she raised one leg high in the air to show that it was in plaster. She had just had surgery, she explained, but was determined to keep going - and so she did, first lying down and then (after being lifted there by assistants) perched on a stool.

The rest of her performance was less interesting. She is the daughter of the great João Gilberto, whose singing and guitar work defined the bossa-nova era of the late 1950s, and she has sold albums by the truckload in the west, but for much of the show she seemed incapable of even repeating the gently sensual pop-bossa format that made her a success.

She managed best with her own English-language ballads such as Os Novos Yorkinos, but failed sadly with the old Caetano Veloso/Os Mutantes favourite, Baby. Most of the other songs were brash or heavy-handed, and accompanied by frantic hand-waving to enthuse her followers.

Towards the end, she was joined on stage by the sparky young Rio team of Kassin, Moreno and Domenico, who had also opened the show. They, too, are known for their musical ancestry - Moreno is the son of the Tropicalia hero, Caetano Veloso - but provide a far more adventurous vision of the new Brazil. All three are inventive singer-songwriters and multi-instrumentalists, and they mixed cool post-bossa vocals with anything from adventurous electric-guitar work to the hand-claps and electronics of Domenico's delightfully quirky Alegria, Vai Lá. It was unfortunate that the dreaded Roundhouse acoustics didn't do them justice.