She spent the day chatting away to professional racing car drivers at the London E-Prix while wearing a personalised race suit. But Cara Delevingne slipped into something a little more glamorous when she attended Formula E chairman Alejandro Agag's dinner party on the Thames on Saturday evening. The star, 28, wowed in a glittering black mini-dress that ensured all eyes were on her supermodel pins, with the thigh-skimming number also featuring striking embroidery of a dragon breathing fire at two angels. Wow: Cara Delevingne, 28, wowed in a glittering black mini-dress when she attended Formula E chairman Alejandro Agag's dinner party on the Thames on Saturday