'I’d sift through the postcards to match them to the characters’ storyline,' Willoughby says. 'It’s like strands of a story coming together' Photograph: Paul Willoughby
'I found a lot of the cards on eBay, some on specialist sites. I used this one for Agent Cooper as he’s the stag character, a sort of alpha male' Photograph: Paul Willoughby
'Audrey was the character I found most fascinating. I found the perfect postcard for her, since she lives in a hotel on the edge of a waterfall' Photograph: Paul Willoughby
'There’s indecipherable writing on a few cards, but I like the fact they’re fractured stories, rather than something really clear' Photograph: Paul Willoughby
'This postcard just felt right for him. Gordon doesn't listen much, because he's got the earpiece in the whole time. He does whatever he wants, kind of like a train chugging along without changing direction' Photograph: Paul Willoughby
'I drew these with a really fine liner. I'd use three different weights of dot, starting with a very coarse dot and moving to finer dots towards the end, to get the highlights and the softer tones' Photograph: Paul Willoughby
'When I started doing these I would keep going and going and going, but you get fatigued. So I started to use the pomodoro technique: you work for 25 minutes then have a five-minute break. It completely renews the sense of what you're doing' Photograph: Paul Willoughby
'Each picture took between two and four hours, probably slightly longer for the finer ones. I would spread it over a couple of days and do it in two sittings' Photograph: Paul Willoughby
