I guess if you have no science background you'd be taken in by this so called documentary.
There are simple errors that lead me to believe the producers do not understand their subject. First, you do not measure past temperatures by inserting a probe into a borehole in a glacier nor do you measure temperatures with using carbon dating. Historic temperatures are measured using oxygen isotope analysis. Carbon dating is used to set the time frame.
With regard to "scrubbing" the little ice age and medieval warm period from the "hockey stick" graph. Both the little ice age and medieval warm period are present in the graph shown in the video, you have to look closely because the changes are just too small to see when you add the temperature rise during the past century. In fact, this tells us that much smaller temperature changes than those that have occurred recently are sufficient to cause major problems for our economy.
The most glaring error is the idea that single tree in the Maldives is evidence that millions of satellite and tide gauge measurements are wrong. First, no evidence was presented to show that there had been no uplift of subsidence in the Maldives over the past 3 centuries. Second, the presenter assumed that the coastline at the tree had not changed since the tree germinated. Odd conclusion since the tree was clearly being undermined, showing clearly that the coastline had moved shore-ward under the tree roots. Third, why did he go to the Maldives, one would think that there are millions of such trees in Europe--if he is correct that is. The skeleton was a complete red hearing because no contextual foundation was laid.
With regard to models. Climate models are calibrated against historical data. If you do not trust climate models do not get on a plane because the climate modellers and airplane engineers take the same physics and math classes and use the same finite element modelling methods.