Ready to Wear: Valentino is the undisputed master of the grand gesture

Nobody would ever accuse the great Roman couturier, Valentino Garavani, of understatement. Instead he is the undisputed master of the grand gesture. As The Last Emperor, a film about his life and work, opens, he announces: "I love a beautiful lady. I love a beautiful dog. I love a beautiful piece of furniture. I love beauty. It's not my fault." Don't you just know how he feels.

This documentary follows its mahogany-skinned protagonist on board his private jet – five pugs and official pug-handler/toothbrusher in tow – taking in the last two years of his career in particular. As the proceedings leading up to his impossibly elaborate and even more excessive 45th anniversary celebrations in Rome unfold, there are childish tantrums, high-camp posturing and tears aplenty. Even the Coliseum plays its part – lit up, for the duration, in Valentino red.

Two months after this anniversary, in September 2007, Valentino's retirement was announced. "The market is asking us to change, to do so many different things, and I'm not sure Valentino wants to do that," says Matteo Marzotti – Marzotti Spa acquired Valentino in 2002. It was taken over by investment brand Permira five years later. Cue: Val weeping once more, having no intention of curbing his extravagant lifestyle or putting his name to any bland, money-spinning scent.

"I don't know what's going on," he mutters. "I'm a little confused."

More stridently: "Valentino is above control. Valentino does what he wants. Valentino is Valentino," says Giancarlo Giammetti and, as the former's right-hand man since 1960, he should know.

For all the footage of glittering parties – Michael Caine, Joan Collins, Gwyneth Paltrow and a braying Elizabeth Hurley all have their moment in the sun or, more accurately, driving rain here – this is a poignant study of that relationship.

Just as Valentino continuously hurls insults at his friend, he pleads with Giammetti to take time out to ski with him in Gstaad. Giammetti, likewise, rolls his eyes at such histrionics, tells an agitated Valentino that he is showing his belly and is even "too brown", but cannot conceal his excitement and admiration for his partner throughout. Like an old married couple, they bicker ceaselessly. This, though, is surely one of the fashion world's most intense and enduring love affairs.

The Last Emperor, 7 June, 10pm, BBC4