The premise: A mammoth from the ice age is frozen in a glacier, and thawed out by a scientist and her kid sidekick. The mammoth, named Phil, can speak perfect English and comes from a surprisingly sophisticated tribe of mammoth scientist/engineers. Each episode, Dr C. and Mike would, in a cold open, encounter a tricky engineering problem with some device, and Phil would tell a story about solving the same problem years ago. Cue titles, then a Flash Back.
The titular Cro was a young human boy (presumably a Cro-Magnon man), whose adopted Neanderthal family was assimilated into the mammoth community. Although the humans were, for the most part, pretty stupid, the mammoths found their opposable thumbs useful.
Each Flash Back would have the mammoths coach Cro and his Neanderthal family through the solving of a problem with some type of simple machine. It differed from the typical Bamboo Technology in that all the devices were built on a foundation of good solid science.
This program provides examples of:
- Amazing Technicolor Wildlife : Selene is a purple Smilodon.
- Beast Man: Bobb, who is the least evolved of the Neanderthals.
- Eternal English: Phil and Cro speak a version of English that is still in use thousands of years later.
- Every Episode Ending: Dr. C's always heading into some kind of extremely perilous situation just as the episode ends.
- Fantastic Racism: Earle, Mojo and (sometimes) Esmeralda, the older mammoths in the herd. Are shown as Conservative and don't really like or trust the humans
- Downer Beginning: And how. The opening sequence starts off with the main family of cavemen being saved from reoccurring villain, a purple sabertooth tiger, by Phil the Mammoth. Then the ground underneath Phil's feet collapses and he seemingly dies before the eyes of his friends when he plummets to his "death". This is made all the more depressing with the knowledge that Phil would not be found for thousands of years, so Cro and company never found out that Phil survived and ended their lives never knowing. Then by the time said Mammoth would be reanimated, everything he knew and loved had long since died, though this never is brought up in the actual series. And if that's not not enough for you, the opening theme song is done to the tune of Paul Simon's "Mother and Child Reunion."
- Hot Scientist: Among the cast is Dr. Celia (or Dr. C), a rather attractive scientist implied to have descended from Cro. At the start of one episode she's in a bikini much to a blushing Phil's embarrassment.
- Hulk Speak: most of the neanderthal characters would talk like this. Complete with the Mongo Pawn In Game Of Life moments:Ogg: That not funny! Not politically correct either!
- Intellectual Animal: Turns out mammoths were all trained science teachers who spoke perfect late 20th century American English. Who knew?
- Last of His Kind: Phil, although he takes it remarkably well. Maybe all the reminiscing helps.
- Literal Ass-Kicking: Cro got a lot of this in "Meal Like A Pig." He was repeatedly gored in the backside by a wild boar (which turned out to be just a baby) and he repeatedly fell off a small cliff and landed on his butt. He got tangled up in a vine and was dragged butt-first over some rocks. What's more, it's implied that his adventure ended with him getting a huge dose of this trope from an entire pack of (adult) boars!
- Logo Joke: After the end credits, a rolling stone square would collide with a stone circle and a stone triangle, causing all three shapes to crumble into the initials "CTW" (short for Children's Television Workshop, the name that Sesame Workshop went by until 2001).
- Predators Are Mean: Played straight. Both the saber-toothed cat Selene and the dire wolves are portrayed as stereotypical villanous predators. Meanwhile the humans show no interest in hunting the mammoths.
- Stuff Blowing Up: One episode was dedicated to gunpowder.
- The Teaser: Involving Phil and the scientists having a problem in the present which cues the flashback
- Title Theme Tune: "So listen as Phil takes us back to wonders of long ago / And weaves a tale of Woolyville and ice-age boy named Cro-o-o-o, Cro-o-o-o... Cro!"