This excellent documentary follows actor David Tennant as he looks for the answer to just why Hamlet has so captivated audiences and minds alike for so long. He speaks to Shakespeare scholars like Stephen Greenblat, Majorie Garber, and Jonathan Bate. He muses with other Hamlets: Jude Law, Simon Russell Beale, and a young actor at RADA. In my personal favorite moment, he actually gets to touch the real copies of the original editions of Hamlet - including one of only two 1603 "bad" quartos in existence.
A film of David Tennant's Hamlet, with Patrick Stewart as Claudius/Ghost, can be see online via PBS.