I've done loads of things people have never seen, dramas on BBC4 and plays upstairs at the Royal Court and the Bush, and because I didn't go to drama school, they gave me an education.

I'm sure that my father becoming seriously ill when I was 14 had a lot to do with my going from chubby to fat.

Every audition I get, I agonise over and I put everything I can into it.

Because I was always a fat child, I got fatter and fatter, and I ended up 18 stone and with a 40-inch waist.

I never mind talking about my dad. I'm proud of who he is, and being his son is one of the things I'm most proud of. To be constantly compared to someone so brilliant, who happens to be your dad, is cool.

I was nervous about playing a lead part in a Working Title romantic comedy and I was also nervous about the fact that I not only had to take my clothes off, but get my willy out. There's certain things you can do to make yourself look better, but there's nothing you can do about your willy. Your willy is your willy and no amount of working out is going to make your willy look any different. You get what you're given. But I wanted to look my best and to whip myself into any semblance of handsomeness. And that was hard going.

I'll probably always be 'Timothy Spall's son' and it's something I'm proud of. Maybe one day as well as that, they'll say of Timothy Spall that 'He's Rafe Spall's dad'.