Actors will go to any lengths to slip into their roles, even if it means going unnoticed on screen. For example, these 20 screen stars’ clever disguises managed to pull the wool over everyone’s eyes.

It’s hard for Hollywood stars to go unnoticed; after all, when your face appears projected on movie screens the world over, even walking down the street incognito can be a challenge. But thanks to make-up or clever costuming, some still manage to take on roles you may not have known they even played – like this little lot.

20. Ari – Planet of the Apes (2001)

While the most recent Planet of the Apes film – 2014’s Dawn of the Planet of the Apes – used CGI to transform its actors into primates, Tim Burton’s 2001 remake stayed faithful to the original’s movie’s use of cosmetics and costumes. And, thanks in part to the sterling effort put in by make-up and effects artist Rick Baker to make Planet of the Apes’ stars more simian, Helena Bonham Carter is utterly unrecognizable as chimp Ari.

19. Pennywise the Dancing Clown – It (1990)

It’s hard to believe that the man who played the too campy to be truly frightening Frank-N-Furter in The Rocky Horror Picture Show also stars as the nightmare-inducing Pennywise in It. But that’s indeed the case – and perhaps Tim Curry’s ability to hide behind the white face-paint, red nose and wig helped him play the 1990 TV movie’s evil, child-killing clown to the hilt and free of any preconceptions.

18. Mason Verger – Hannibal (2001)

Mason Verger stands as a terrifying reminder of Dr. Hannibal Lecter’s cruelty in Ridley Scott’s 2001 sequel to The Silence of the Lambs. Playing the disfigured former victim in Hannibal, however, is none other than an incognito Gary Oldman, whose convincing portrayal is aided by make-up technician Christopher Gallaher’s effects.

17. Marlene McFly – Back to the Future Part II (1989)

We all know Michael J. Fox as Back to the Future’s hero Marty McFly, but how many caught him in another role in its 1989 sequel? Two other roles, in fact: in Back to the Future II Fox pops up as both of McFly’s future children, Marty Jr. and Marlene. Yep, that’s right – the star plays a teen girl and is so strangely convincing that perhaps he should drag up more often.

16. Unkar Plutt – Star Wars: The Force Awakens (2015)

2015 blockbuster Star Wars: The Force Awakens features some surprising cameos from starry names – and the man inside the suit of Jakku junkboss Unkar Plutt is no exception. Star Wars superfan Simon Pegg is in fact the actor that portrays the Crolute trader, albeit hidden under a heavy costume that must have been pretty darn hot to wear. No wonder Plutt is so grumpy.

Image: YouTube/Sony Pictures Entertainment

15. Boris the Animal – Men in Black 3 (2012)

If you didn’t know who plays Men in Black 3’s ferocious alien villain Boris the Animal, you would probably identify any number of actors famous for portraying hard men or action stars before Jemaine Clement. Yep, that’s right – the laid-back Flight of the Conchords star is the man behind the beard, camera lens eyes and terrifying teeth, transformed in part by the handiwork of Rick Baker for the 2012 sequel.

Image: YouTube/DisneyMoviesInternational

14. Davy Jones – Pirates of the Caribbean: Dead Man’s Chest (2006)

Davy Jones was a memorably gross villain in the 2006 sequel to Pirates of the Caribbean, in no small part down to his beard of wriggling tentacles. And, believe it or not, it’s British actor Bill Nighy who plays the gruesome human/sea creature hybrid in Pirates of the Caribbean: Dead Man’s Chest using a mixture of live action and motion-capture technology – and eventually fleshed out in CGI by visual effects giants Industrial Light & Magic.

13. Beast – X-Men: The Last Stand (2006)

X-Men: The Last Stand saw genius mutant Beast make a splash on the silver screen, and a suitably intellectual actor plays him. Frasier’s Kelsey Grammer is unrecognizable in the role in Brett Ratner’s 2006 superhero flick, thanks to strikingly blue hair and make-up that took up to three hours to apply.

12. Frank – Frank (2014)

Lenny Abrahamson’s kooky 2014 dramedy Frank features a very big name in a very secretive role. It’s Michael Fassbender who plays the eccentric eponymous musician; not that you’d ever know, mind you, as Frank’s schtick is that he keeps that strange fake head on all the time – even when he’s showering.

11. Kona Chief – Cloud Atlas (2012)

The Wachowskis’ 2012 sci-fi epic Cloud Atlas features huge stars of the likes of Tom Hanks playing different characters throughout a vast timeline. Hugh Grant is one of them – although you’d be hard-pressed to recognize him straight off the bat as the Kona Chief, the head of a tribe of brutal cannibals in a post-apocalyptic version of Earth. After all, he’s more than a little different from the bumbling rom-com heroes for which Grant is best known.

10. Ethan Roark Jr. – Sin City (2005)

Yellow-skinned pedophile Ethan Roark Jr. is without doubt the foulest character in Robert Rodriguez’s Sin City. It seems strange, then, to learn that it’s dashing Terminator 3: Rise of the Machines star Nick Stahl who plays the jaundiced creep in the 2005 comic book adaptation, ably disguised by some stomach-turning prosthetics.

9. Violator – Spawn (1997)

Violator is a small, overweight demon clown sent by Hell itself – the obvious choice, then, to be the chief antagonist of 1997 comic book adaptation Spawn. Not so obvious, though, was the casting choice for the role. Likeable John Leguizamo was the one who had to squeeze into Violator’s prosthetic make-up and costume – a feat which the actor has likened to being wrapped in a certain, ahem, prophylactic device.

Image: YouTube/The Baltimore Movie Trailer Park

8. The Creature – Mary Shelley’s Frankenstein (1994)

Dr. Frankenstein’s Monster has received its fair share of movie portrayals, most notably by Boris Karloff in 1931. For his 1994 adaptation of Mary Shelley’s classic tale, however, director Kenneth Branagh presented a more sympathetic monster – and chose none other than Robert De Niro to bring the role to life. Not that you’d ever guess it was the veteran star, though, under all that realistic-looking scar tissue.

7. Lord of Darkness – Legend (1985)

Ridley Scott’s fantasy-adventure flick Legend has one of the best representations of the Devil in any movie, and that’s down to an actor who, once again, can’t really be identified by sight in the 1985 feature. Years before playing Pennywise, Tim Curry stepped up to the plate to portray the rather exuberant Lord of Darkness, seemingly unhindered by the giant horns and red body paint that he had to don.

6. General Thade – Planet of the Apes (2001)

Helena Bonham Carter wasn’t the only star going unnoticed in Tim Burton’s 21st century reboot of Planet of the Apes. Tim Roth also slips under the radar as the villainous General Thade; perhaps that immaculate make-up helped him channel his inner primate.

5. The Thing – Fantastic Four (2005)

Amazingly, it’s The Shield’s Michael Chiklis who portrays rock-solid superhero The Thing in 2005’s Fantastic Four. Before Chiklis could even step onto set, though, he had to spend grueling hours in the make-up chair. “I dealt with it through comedy,” the actor has admitted. “I end up ranting schtick and making [the make-up artists] laugh while they attack me physically.”

4. Kirk Lazarus – Tropic Thunder (2008)

Tropic Thunder parodies the insane lengths actors go to in order to nab an Oscar and Kirk Lazarus – a super-dedicated Australian actor who actually changes the color of his skin to play an African-American soldier – is the comedy film’s ridiculous highlight. In an amusingly ironic twist, Robert Downey Jr. actually received an Academy Award nomination for his performance in the 2008 movie.

3. Miracle Max – The Princess Bride (1987)

Even though Miracle Max only shows up towards the end of The Princess Bride, the elderly healer has become a fan favorite thanks to his witty one-liners. However, even those fans of Rob Reiner’s 1987 fantasy classic might not know that the character was actually portrayed by a prosthetics-wearing Billy Crystal – who brought a snap of his own grandma onto set in order to help craft Max’s rather unique look.

2. Ronan the Accuser – Guardians of the Galaxy (2014)

Hobbit fans may be surprised to hear that the same actor who plays Thranduil also portrays the depraved Ronan the Accuser in Guardians of the Galaxy. Lee Pace hunkered down for a long spell with make-up artists on the set of the 2014 superhero movie – all worth it, since the alien judicial officer’s appearances gives him quite the air of otherworldly menace.

1. Roy “Rocky” Dennis – Mask (1985)

To accurately recreate the craniodiaphyseal dysplasia of Mask’s protagonist Rocky Dennis, the 1985 movie’s make-up designer Michael Westmore crafted a facial disguise out of latex. That prosthetic may have helped Mask win an Academy Award for make-up design, and it certainly helped Eric Stoltz to be completely unrecognizable when playing the disfigured teenager.