Documents found on a North Korean server suggest US studios may have unknowingly outsourced animation work | CNN Politics
www.cnn.com
North Korean illustrators and graphic designers appear to have helped produce work for US animation studios unbeknownst to those companies, suggesting that unreleased episodes of a few popular American cartoons could include work from one of the most closed-off economies in the world.

Sketches and animation directions, including for upcoming Invincible episodes, were found on a North Korean server.

This would imply that some of the animation work was outsourced down the chain illegally to extremely low paid North Korean animators.