I finished watching all ten of the Dekalog films by Krzysztof Kieslowski. There is a helpful synopsis and introduction of the films on the Facets Multimedia website.
Overall I found them to be really interesting and thought provoking. For a ten-film series, each with its own cinematographer, the collection of films is remarkably consistent. The stories are disturbingly interesting and the acting is very good.
My pick for the best five of the ten movies to be 1, 2, 3, 5, and 7.