Madonna made a surprise appearance last night at the London premiere of Guy Ritchie's new film RocknRolla. Despite being in the midst of her world tour, Madonna appeared on the red carpet in a black bejewelled Stella McCartney dress. Back in May Madonna hit the red carpet with Guy in a different Stella McCartney dress. Maybe Madonna thinks that Stella McCartney dress + Guy Ritchie = good red carpet experience! What do you think of her look?