Sunday 22 February

The Big Day. At breakfast, David Hare (nominated for adapting The Reader) and screenwriter Danny Strong (Recount) insist that my category is wide open, and I stand a good chance. Still unconvinced.

This is my fourth film at the Oscars, and our 13th nomination. Of these, I've had six personally - twice as director, four times for original screenplay. Our only two wins were for Topsy-Turvy's costumes and makeup.

What a strange, surreal experience it is. A tremendous honour to be nominated - but then you trek across the planet, you squeeze into your tux, you squeeze into a stretch limo, you squeeze through the security tent on to the jam-packed, chaotic red carpet, and then you sit through a very long show (which turns out this year to be far less tacky and schmaltzy than usual). At one, weird moment, some strange force suddenly convinces you that you're about to win, while you affect to look benign and generous for the camera that's suddenly in your face; then you don't win, and you spend the rest of the night trying to be grown-up and sporting. You even try to enjoy yourself.

And here I am again, trundling through Hollywood in a black stretch, but it's huge fun as Toby and Leo find it all such a gas.

This year, the demonstrators near the awards include anti-gay factions protesting against Milk. When we were here in 2005 with Vera Drake, we were happy to be hijacked by an organisation called Bastard America, whose cause was the fight for adopted people to be allowed to trace their birth mothers.

We're held up in the security marquee where we have to show our passports; Toby chats to the guards, who turn out to be US squaddies on a jolly day's secondment. Werner Herzog, next to me in the queue, tells me he starts shooting next week in Santiago. I'm amazed.

Red carpet chaos. Few TV crews are interested in me, though I do an interview with Lisa and Joey (TV Guide channel), who tell me how I work with actors (it's available on YouTube). There's some paparazzi posing with the boys, then quite a long wait with drinks, and into the 81st Academy Awards show. Toby sits with me, Leo nearby. Later, they swap. I'm next to Peter Morgan (up for Frost/Nixon adapted screenplay) and Martin McDonagh (In Bruges original screenplay), both of whom I admire.

The screenplay categories are early. We're third in, and it's exactly as I've described.

The cameraman lining up my close-up checks that I'm me, which I immediately decode as a sign that I've won. Hey presto - it's that moment again! What am I going to say? I should have written a speech ...

"And the Oscar goes to ... Dustin Lance Black for Milk!" A nice guy - I met him a few weeks ago at the New York Critics' awards (me best director, Sally best actress), and I like Milk a lot. Dustin makes a great speech, an important moment for gay rights.

The truth is, you only really get the loser's hump about the winners if you think that they're crap, and tonight I get a real buzz out of nearly all the awards. Chuffed for jolly Michael O'Connor (best costumes, The Duchess), who assisted Lindy Hemming on Topsy-Turvy, and delighted that Benjamin Button only got technical awards! Wanted Mickey Rourke to win best actor (I voted for him) and, no disrespect to Kate and the other girls, I desperately miss Sally. I genuinely can't see how any of their performances are as original, creative, profound, witty or versatile as hers. But there you go.

A great night for the Brits. I revel in Slumdog's triumph. So happy for Danny. And the unsung heroine is the great Tessa Ross of Film4, who initiated Slumdog and has been the warm, nurturing supporter of so many of our films.

Afterwards, the Governor's Ball and the Vanity Fair party. Toby and Leo exhort me to say hello to Robert De Niro. So I do. I can't tell if he knows who I am, but the guys get to shake his hand. Lots of chats with celebs various, but I haven't got time to describe it. And loads of people say very nice things about me and my work.

Finally ... Toby and Leo greet two of the little Slumdog kids:

Leo: "Well done, lads."

Toby: "Give me a high-five!"

Smallest kid: "No, no; 10-five, 10-five!"

And Toby duly obliges.