If you've seen any big blockbuster movie lately, you know just how impressive computer effects can be.
These days the only limit to what you can put on screen is your imagination.
But to make those colorful CGI characters come to life, you still need actors to take their place.
Before Hollywood's computer wizards do their magic, the typical movie set looks pretty strange - and these hilarious photos prove it.
1. Good boy
2. Are you telling me they don't use real flying books?
3. Close enough
4. Teenage Mutant Ninja Turtles and average, adult actors in suits
5. Nice shoulder pads
6. They had to digitally remove some of his cheeriness
7. Feeling blue?
8. Don't let this role give you a big head, Lupita
9. Acting still takes a lot of imagination
10. Suddenly, they're not so scary
11. Got your nose!
12. Did you two forget your suits?
13. It's a bird, it's a plane, it's not that impressive up close
14. He gets really into character
15. Are you telling me they didn't hire a real dragon?
16. Can you spot the difference?
17. Smile, you're on camera!
18. Another job lost to a robot
19. Not so beastly behind the scenes
20. It's not easy being green
21. Something's fishy about these guys....
22. Curious and curiouser
23. He toughened up a bit
24. Not as cuddly as he seems
25. Tapping into her wild side
26. Some assembly required
27. Four years in acting school, all for this...
For more glimpses behind the scenes in Hollywood, check out movies before the special effects are added.
And see 10 actors who totally transformed to play real people.