Mad Jack is Joe's other maternal uncle and the brother of Uncle Joe and Joe and Anna's mother. He believes the book is rightfully his and will do anything to get it so he can rule all of eternity. He can be seen in the background of every single episode. He only appears in the TV show. He no doubt has an estranged relationship with his family as Joe and Anna never knew about him before he introduced himself. Eventually he will have a big showdown with his nephew but this is never seen as the show was cancelled.
First appearance: The Not so Jolly Roger (cameo)
First appearance as a main character: The Seven Blunders of the World.
Last appearance: Plaid to the Bone
Mad Jack has appeared in almost every episode to date.
He been a main character in 7 episodes:
Plaid to the Bone
Break an Egg
Breaking the Codex
The Seven Blunders of the World
and Sam, Samurai.
Here is a list of cameos:
2105 (museum croud)
Jinga All the Way (guard)
Able Was I Ere I Saw Elba (dress)
Me Oh Maya (on vaction)
Hey Kid, Want to Buy a Bridge? (on a Penny Farthing)
Lewis and Clark... and Freddi, Jodie, and Samantha (explorer)
Tut, Tut (relaxing) NOTE: appears for 2 seconds
You Can't, But Genghis Khan (servant)
The Not So Jolly Roger (crew member)