The laws of probability seems simple at first thought, but scratch the surface and their inner truth can be rather more counterintuitive. This video describes one of those situations—and the answer might prove more useful than you think.

In this alternative to really nice new recasting of the Monty Hall problem by New Scientist, the stakes are high: understanding probability could help a fictional you make the a decision that could save your life. So, how do you choose? Let the video play through and choose your own ending to find out. [New Scientist]