A very good documentary about the lives and struggles of several families of polar bears through the first year of their cubs. The cinematography, storytelling and pacing is almost up to the standard of a big BBC documentary series. David Tennant provides the narrative in his native Scottish accent, which may be a bit distracting at first.The "stars" of this documentary are not just the bears, but also the very innovative "spy cameras" that are used to track and film the daily lives of the polar bears up-close. This provides not only a novel perspective, but also some fun moments, as the ever-curious bears initially investigate the remote-controlled cameras until they get used to them. The cameras are camouflaged to look like objects in the natural surroundings, and once the bears ignore them, they go about their business uninhibited. This, and the remarkable picture quality of these mobile cameras, allows for an unprecedented level of closeness.The pacing is good and given a number of quite funny moments, it should hold the attention of younger viewers as well. Environmental concerns are hinted at, but not pushed like in some other documentaries. True to its title, this is primarily a documentary about polar bears and should be interesting and captivating for anyone with even a slight interest in them.