Tib belongs to the Big Rock Tribe of cavepeople. Despite being a member of a tribe, he feels as though he doesn't really belong - it mostly has to do with the odd-shaped, red, round birthmark on his eye - which all the other kids in the tribe make fun of. Tib's parents just don't understand, so he wanders off into the woods to be alone for a while and runs head-first into a dinosaur! Just one problem... aren't dinosaurs supposed to be extinct? This dinosaur in particular seems friendly enough as he begins to follow Tib around, which is when Tib realizes that they both have similar markings on their faces - wait until all the members of his tribe see his dinosaur! No such luck. Just when Tib thinks that he will be able to share his dinosaur, that same dinosaur manages to find a way to hide! Tib tries every trick in the book to get members of his tribe to meet his him, but he is just too good at hiding. Nevertheless, Tib and Tumtum the Dinosaur still end up having many fun adventures together - even though everyone thinks he doesn't exist!
The comic book is very funny and the accompanying illustrations just add to the hilarity. Grimaldi's story is very thoughtfully put together with an important message about friendship and not caring what somebody looks like on the outside. Bannister's drawings are clever and full of action, bringing Tib and Tumtum to life on the pages. Readers of all ages will enjoy this color-panel comic.