Rachel Weisz said she will always associate Colin Farrell with his Lobster alter-ego as they attended the new film’s premiere.

The Irish star, 39, had to pile on the pounds to play David in the unconventional love story, directed by Yorgos Lanthimos as his English-language debut, in which the pair play two people who fall in love.

Rachel, 45, said on the red carpet outside Vue West End cinema: “I’d never met Colin before. I met when he had the increased weight and his face and his jawline were like doughy flesh so he will always be David to me.”

Colin said he didn’t enjoy the weight gain.

Colin Farrell
(Matt Crossick/PA)

“It was not really a joy because you’re just eating for eight weeks. I didn’t want to put on weight because I didn’t want to work to lose it so I was saying to Yorgos, ‘What about if he’s really thin?’ Because I did want to alter my physicality somewhat.”

The Lobster, also starring Olivia Colman, Ben Whishaw and Jessica Barden, feature characters staying at a hotel who have to find themselves a partner within 45 days in a life or death situation.

Rachel Weisz
(Matt Crossick/PA)

Rachel – whose character is described as Shortsighted Woman – said: “I don’t think the plot of the film is to be taken seriously. It’s very absurd.

“It’s more about how we all live like sheep and we follow rules and nobody really steps out of line. It’s a very original film about how hard it is to be original.”

Colin added: “Love at first sight is possible and it’s a quicker time than that but the film asks questions about aloneness, coupledom and singledom. People can make whatever decisions they want after they’ve seen the film. That’s another way of saying I don’t know.”

Olivia, who plays the hotel manager, said: “For some people it would be possible. It’s not an ideal way of doing it, being forced into it. It’s a fun notion.”

Rachel Weisz and Colin Farrell
Matt Crossick/PA)

Rachel also revealed how she has yet to see Spectre, the new 007 adventure starring her husband Daniel Craig as James Bond.

She added: “He finished filming Spectre in June so I’ve had him back for a while now.”

The Lobster opens in UK cinemas on October 16.