The Little Britain star donned a false belly and stick-on warts to play Toad in the new BBC One version, which will be broadcast over Christmas.
He said: ‘Toad is a wonderful iconic character. He's a dandy and a wastrel and I'm very grateful to do it. It really is a prize role
‘I have green marks on my head and transfers for tattoos which I had to get done every day. It's an hour in make-up but it's better than doing Bubbles in Little Britain, which took four hours.
"I have strange eye sockets that make me look quite different, with enlarged eyebrows, and to get inside the skin of Toad I use gestures that are toad-like.
‘I did a lot of work with Marcello Magni from Theatre de Complicite and we explored the movements of animals and the noises they make. I also looked at a lot of toads and they don't move that much, whereas Mr Toad is terribly excitable and moves a lot. So I try to make the eyes go big, and keep the neck stiff.’
At one point in the story, Toad has to escape from jail dressed as a washerwoman. ‘I got to dress up as a woman again!’ said Lucas.
“Toad is a fanatic – he loves boats, planes, horses, whatever. He pounces on something and evangelises it, then gets bored in a few days and moves on to the next thing. I can get like that, too. I was so pro-England in the World Cup and then, as soon as we lost, I lost interest also.
‘To some extent I can identify with Toad. He is a buffoon and he is pompous, but he's also affectionate. I also have the shape of Toad with my own little belly, and then another one added by the costume department.
‘It's not great in terms of personal vanity, but then I have played a watermelon with Vic and Bob, and been in the romper suit in Shooting Stars, so after that you don't have an ego or vanity. Costume is sometimes cumbersome, but always worth it.’
Filming reunited Matt with the League Of Gentlemen’s Mark Gatiss, who plays Ratty.
‘Mark and I have been friends for years,’ Lucas said. ‘He was the script editor on the first series of Little Britain.
‘Then Bob Hoskins came along as Badger – and, as I grew up watching The Long Good Friday and Who Framed Roger Rabbit?, it has been a great privilege to work with him. The chemistry between us is good and I hope that spills over to the screen.’
