My style has changed over the years. I used to feel shy at red-carpet events – the fact that everybody’s looking at you and your outfit is commented on. I’d wear a tuxedo or something you couldn’t argue with, and I used to try to cover everything up as much as possible. But after a while, I thought: “No, actually, I’m going to bloody well go for a proper evening gown!” This dress was one of the first results.

As soon as I saw it, I thought, “Oh my God, that looks gorgeous.” I had asked my stylist, Jillie Murphy, to help me find something to wear to the 2015 Baftas, where I would be presenting an award with Ralph Fiennes. I didn’t want anything gathered in at the waist because I haven’t got one. I said I’d prefer a column dress, and she got me several fantastic options, but this Adrianna Papell gown stood out. This dress was a pale grey and very shimmery in a way that the others I tried weren’t.

There is nothing more depressing than going along to a fitting: they shout out all your measurements, and then nothing they give you fits. But this dress was perfect, and that was a great feeling. Jillie also gave me the black shawl, which hung so beautifully and really added to the look. I didn’t want to cover the dress up but the weather wasn’t marvellous and it was just right. There have been times when I’ve worn things and the straps keep falling down or your sleeve keeps going in your dinner, or I just haven’t felt it was a good look for me.

I felt great walking on to the stage. But I can't go to Waitrose in it

Now I quite like getting dressed up – I’ve got a bit more confident. Everyone asked me who designed this dress and apparently requests were still being made for it a year later.

I felt great walking on to the stage. I was allowed to keep the gown but I’ve not worn it since – there aren’t many places you can wear a dress like that. I can’t go to Waitrose in it.

• Julie Walters stars in Wild Rose, released on 12 April