Why is MirrorMask rated PG?
Official MPAA Rating: MirrorMask is rated PG for for some mild thematic elements and scary images.
The uncertainty of having a seriously ill parent is compounded by the strange images the teenaged girl encounters in her dream world. While the violence is limited, the bizarre computer graphics (despite their amazing craftsmanship) makes the visuals appear rather frightening. These include a spreading, tentacle-like darkness that turns several characters into stone (they disintegrate after this happens), creatures that look like an eyeball with spidery legs, hostile hungry sphinxes, and monkey-birds that hit one another with their beaks. As well, a character is betrayed and kidnapped. Also, some harsh words and kisses are exchanged between characters in the real world.