It's clear that many actors relish the opportunity to get deep into character when shooting a movie, whether through method acting or a more hands-on physical transformation through makeup, costumes, and so on.
Some actors take this even further by using their transformation to effectively disguise and hide themselves from the audience, ensuring their presence is only noticed by the most observant of viewers.
In some cases the performers were even allowed input on their makeup and prosthetic design, at which point they pushed things much further than just about anyone expected.
For good measure, they might've also taken the part uncredited to make their presence that much tougher to detect.
While these parts were all spotted eventually, to casual viewers they were easily missed, because it's incredible how thoroughly a scraggly beard or a face full of slap can change an actor's entire visage.
As much as many actors want to make sure their name and face are front-and-center at all times, these performers took the less-vain, more playful approach of wilfully disappearing into the scenery, and presumably got quite the kick out of it...
10. Andy Serkis - Long Shot
You'd be forgiven for not even realising that Andy Serkis had a small cameo appearance in the Seth Rogen-Charlize Theron rom-com Long Shot, playing ethically dubious (at best) media mogul Parker Wembley.
When Serkis was offered the part, he was originally supposed to play it as himself sans-makeup, but Serkis insisted that he undergo an extensive transformation in the makeup chair in order to get into character. Director Jonathan Levine said:
"Andy Serkis made choices that nobody asked him to make, and that sounds like a negative thing, but as a director, actually, that's one of the most beautiful gifts you can give a director. Because he really dove into the character, and he really wanted to make it his own.
The biggest thing was that he decided to be in prosthetic makeup for six hours a day. But you start to realise that this is how Andy Serkis accesses characters. If you think about Andy Serkis' career, it's facial expressions; it's very primal stuff. And so that really helped him figure out this guy."
Hilariously, Rogen himself said there were even occasions where the film's shooting schedule would get switched around, and so Serkis would spend a huge chunk of his day getting makeup applied for nothing.
The end result certainly helps accentuate the sliminess of Serkis' character, while distracting the audience from the fact they're actually looking at Andy Serkis at all.