If Ben Stiller has done anything smart for Zoolander 2, his long-awaited sequel to his hilarious 2001 fashion world comedy, it’s casting Penélope Cruz. When we meet in a London hotel, the 41 year-old Spanish siren has already been furiously working the red carpets in Berlin and her native Madrid, understandably grabbing all the attention of the photographers (and who can blame them, when the alternative is snapping the somewhat less photogenic Stiller and his co-stars Will Ferrell and Owen Wilson?).

It cuts both ways of course. Cruz was a huge fan of the original movie and this was her chance to hang out with Stiller’s braindead male model Derek Zoolander and Wilson’s fellow catwalk Himbo, Hansel.

“I’m so happy because I was there with Derek and Hansel,” she grins, today wrapping her slim frame in a beige cardigan and explaining that she spent half her time on set using Dubsmash, the app that allows users to record video selfies cut to existing audio, producing her own really, really good-looking Zoolander quotes.

Playing Valentina, an agent with Interpol’s Global Fashion Division, Cruz’s character gets involved with Derek and Hansel just as a mysterious villain is killing pop-stars (in an opening sure to be popular with any music lover, Justin Bieber gets gunned down). Valentina has her own fashion secret: she used to be swimsuit model, something Derek and Hansel feel is tragic.

“I think it’s one of the funniest things,” says Cruz, “that she is traumatized that she never made it into high fashion.”

Cruz, on the other hand, has the ear of fashion’s elite. “I’ve got to know well many of the designers – like Galliano, Oscar de la Renta, Armani, Dolce & Gabbana,” she explains. She’s even launched her own lingerie range L’Agent by AP with her sister Mónica. “The line is expanding so much,” she says. “Now we have stores in so many countries all around the world and it’s really growing.” Not one to miss a trick, Cruz’s character in Zoolander 2 can be glimpsed wearing “a very tight corset” from their line.

With all this insider knowledge, Cruz has great admiration for the fashion world – despite its outlandish theatricality being ripe for mockery. “I’ve spent time and seen what goes on behind and it’s so much hard work, so much creativity, so much delegation,” she says. “Those designers work extremely hard and they are really talented, so there is nothing to laugh about that part of the industry. But there is another part of it – material that you can joke about.”

For Cruz, Zoolander 2 represented a rare opportunity – to work in the field of broad comedy. While her work for Woody Allen (on Vicky Cristina Barcelona, which won her a Best Supporting Actress Oscar, and To Rome With Love) and her five films with Pedro Almodóvar (including Volver and Broken Embraces) contain humour, she’s never been this wild.

“I always look for different things,” she shrugs. “It’s not like I’m only reading dramas. But I get more dramas than comedy, especially in the last few years.”

Curiously, she went directly from Zoolander 2 to a small role in Grimsby, the upcoming new film from Britain’s own comic genius, Borat and Ali G creator Sacha Baron Cohen, in which he plays a loutish football fan. And who does she play?

“It’s a really mean character!” she says, coyly. “She’s from her own world and she has many different faces.” Having become a mother – she and her actor-husband Javier Bardem have a son Leonardo, 4, and a daughter Luna, 2 – did she feel the need to seek out lighter fare?

“It wasn’t like that,” she says. “After I had my daughter, when she was a year old, then I did Ma Ma – which is coming to the UK soon. This is one of the most hardcore dramas I’ve ever made. This is about breast cancer and a woman that is very ill. She has a son and she fears the son might be alone if something happens to her. It’s a beautiful film but very hard. It’s full of light and full of love but to go through that experience was not easy. I did that and then these…I needed these so much!”

While Cruz is notoriously tight-lipped when it comes to talking about Bardem – they first met on Cruz’s 1992 film debut Jamón Jamón but didn’t get together until Vicky Cristina Barcelona – she’s more relaxed chatting about their offspring. Would she consider making more family-friendly fare so their kids can see what she does?

“Well I have the Pirates of the Caribbean movie I did [2011’s On Stranger Tides] that they can see when they’re older. But you cannot really plan. You just read what comes along and then try and do whatever represents a new challenge for you.”

Primarily based in Madrid, where she grew up the daughter of a hairdresser and an auto mechanic, Cruz is about to start shooting The Queen of Spain, another comedy and a sequel to 1998’s The Girl of Your Dreams, the charming fantasy that won her the first of three Spanish Goya awards.

“It’s the first time I’ve played the same character twice,” she remarks. “This is interesting – over the years, what has happened to that person?” I point out that Danny Boyle is planning the same with Trainspotting, revisiting Irvine Welsh’s characters two decades on. “Really?” she says, unawares. “Wow! That movie was great and so painful to watch.”

Perhaps Boyle can find her a role amongst Leith’s finest.

Zoolander 2 opens tomorrow. Grimsby opens on February 24.