My 9-year-old just discovered this show and absolutely loves it! I find it educational, interesting, and fun. From the episodes I've seen, the brothers (Chris and Martin) start and end the show in real-life filming. The middle of the show switches to cartoons of the brothers, who go on some wild adventure related to the animal of the day. This adventure always involves a wacky suit with super animal powers specific to the animal of the day. While the brothers are the ones in the field with the animals, in the cartoon segment there are two engineer girls who are making the super suits and coming to the rescue occasionally.
There's usually a mild villain who tries to capture an endangered animal to eat, or somehow fashion animals into accessories. That sounds a lot more disturbing than it's presented in the show. For instance, in the lizard show, the villainess zapped the lizards with a sort of freeze ray, which would position them as a belt or handbag decoration or some sort of thing like that. When the freeze ray was released, the lizards all skittered away unharmed.