Some very mild innuendo where two books kiss. One book says "do you want to curl up with a good book?" this is intended to be a sexual advance. This will go over most children's heads.

None of the violence is that graphic: Richard is attacked by an evil man (Mr. Hyde) with a cane. But he misses. One of the characters (Horror) is hanging from a chandelier which falls on Mr. Hyde. He then falls through a hole in the floor.

Captain Ahab tries to attack Moby Dick (a sperm whale) with a spear and the whale leaps into the air above the water and crushes Captain Ahab and his men. The whale then attacks the boat Richard is in and it seems that everyone except Richard and Adventure has met their doom. Later, it turns out that Fantasy and Horror didn't die.

On Long John Silver's ship, Tom Morgan threaten to slice Richard's throat open, but Silver says no. When they get to Treasure Island, the pirates find only one gold piece and decide to try to kill Silver. Horror and Fantasy arrive and beat up all the pirates. Richard picks up a sword and tells Long John Silver to get in the boat near the shore.

A fire breathing dragon swallows Richard and also burns Adventure. But Richard escapes with his friends.

One use of bloody. "She's a bloody nightmare".

One use of damned.

Dr. Jekyll offers a drink to Richard and his friends. Adventure asks for one thinking it's an alcoholic beverage. Horror asks for the olive that is in the drink but Adventure says, "Stand back. This is a man's drink." It turns out to be toxic and makes a hole in the floor. Later, both Horror and Captain Silver issue the line, "Yo! Ho! Ho! and a bottle of rum."

There's one scene at the beginning where paint melts from the mural on the library's rotunda ceiling into a flood and goes after Richard before turning him and the live action library into animated illustrations, which may be frightening. It also has one creepy bit where the paint briefly shapeshifts into a dragon before it chases Richard through the library.

The mood of the live action scenes at the beginning is overall dark and creepy. The thunderstorm that happens when Richard rides on his bike and ends up lost at the library may be intense. During an earlier thunderstorm, a tree scares Richard when he sees it through his window.

Mr. Hyde might be scary to younger viewers. The scene where Moby Dick crushes Captain Ahab and his men may be unsettling. The fire breathing dragon may also scare some kids. But it isn't really worse than what's in other fantasy movies.