A 17 year old mouse with dark brown fur. He's outgrown the rags he used to wear as a kid, but in the interest of blending in he often wears common casual clothes. He wears oversized glasses on the bridge of his snout and a long cream colored scarf around his neck. He is smaller in stature compared to Eli , but more muscular.

Jack seems different from the last time Eli has seen him. Not only can he sneak up on folks without them noticing, but he can hold himself in a fight as well. There is something he's hiding that keeps him from letting Eli get too close when they meet again.