Image copyright Universal

The first two Despicable Me films were hugely successful at the box office - but the forthcoming third instalment finally reveals a long held secret.

Gru - the loveable Steve Carrell-voiced character at the centre of the franchise - has a twin brother we never knew about.

Dru has a lot more hair than his sibling and is considerably more cheerful - a personality trait which sometimes rubs his brother up the wrong way.

But despite that, the pair team up in the film for an adventure we couldn't possibly give you any details of here lest we attract the ire of the spoiler police.

The despicable duo join a long list of famous twins.

Image copyright Getty Images / Reuters

But unlike Jedward, The Proclaimers and Mary Kate and Ashley Olsen, many twin siblings of showbiz figures choose to stay out of the limelight.

Here are eight famous faces you might not have known have a twin.

1. Scarlett and Hunter Johansson

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Scarlett Johansson is one of Hollywood's most recognisable faces - starring in films such as Lost in Translation and Vicky Cristina Barcelona.

But she also has a considerably taller twin brother named Hunter - who often appears alongside her on the red carpet.

He spends his time working with charities and helping with political campaigns - and in 2008 he helped to get President Obama elected.

2. Vin Diesel and Paul Vincent

Image copyright Getty Images / Vin Diesel

Few people know Vin Diesel (whose real name is Mark Sinclair Vincent) has a non-identical twin brother who is also in the entertainment industry.

Paul Vincent generally stays out of the limelight, but in 2013, Diesel posted a picture online of his twin brother with the late Paul Walker, his former Fast and Furious co-star, captioning it: "The two Pauls."

3. Kiefer and Rachel Sutherland

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Kiefer Sutherland is an impressive chap. As his most famous role unequivocally proved, he can last a full 24 hours without eating, sleeping or going to the bathroom.

But one lesser-known thing about the actor is that he has a twin sister called Rachel, who works as a post-production supervisor.

4. Laverne Cox and M Lamar

Image copyright Reuters / Netflix

Orange is the New Black star Laverne Cox made history in 2014 when she became the first transgender person to be nominated for an Emmy acting award.

Her character in the prison drama, Sophia Burset, is also transgender - and in the first series we saw a flashback to before she transitioned, when she was a firefighter called Marcus.

As Cox was relatively unknown at the time - least of all a trans actress - you may have thought some clever make-up was used to make her look like him.

But in actual fact, her twin brother - musician M Lamar - was hired to play Marcus in a perfect piece of casting.

5. Ashton and Michael Kutcher

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Ashton Kutcher is well known for Punk'd and The Butterfly Effect, but he also has a twin brother named Michael - who was diagnosed with cerebral palsy as a child and had a heart transplant at 13.

"My brother was born with cerebral palsy and it taught me that loving people isn't a choice and that people aren't actually all created equal," the actor explained recently.

"We're all created incredibly inequal to one another, in our capabilities and what we can do and how we think and what we see. But we all have the equal capacity to love one another."

6. Linda and Leslie Hamilton

Image copyright YouTube/TriStar Pictures

Hey, remember that time in Terminator 2 when the T1000 morphed into a clone of Sarah Connor in an attempt to lure and kill her son, but was stopped at the last minute by the real Sarah Connor turning up and saving the day?

Great! Us too.

You may have thought that it was done with a bit of CGI help - but it was actually Linda Hamilton's twin sister Leslie who appeared on screen.

Usually, when a Hollywood script demands someone who looks exactly like you to appear on screen at the same time, special effects are used.

Actors who appeared to have a twin on screen but were actually helped out by some post production techniques include Lisa Kudrow playing Phoebe and Ursula in Friends and Armie Hammer playing the Winklevoss twins in The Social Network.

7. Will and Rupert Young

Image copyright Getty Images

Will Young is one of the UK's most successful contestants to come out of a TV talent show, having won Pop Idol in 2001.

But you may not know he also has a twin brother called Rupert.

Not to be confused with the Merlin actor Rupert Young, Will's brother mostly avoids the showbiz world. But he would make an excellent red life jackets model, should he ever fancy a career change.

8. Rami and Sami Malek

Image copyright Getty Images

Mr Robot star Rami Malek became the first minority actor in 18 years to win the Emmy award for best leading actor last September.

He also has a twin brother named Sami, who works in Los Angeles as a teacher. Rami and Sami. Amazing.

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