My latest MSN DVD column takes a look at the deep, rich darkness of “Harry Potter and the Half-Blood Prince” — the first “Potter” film since “Prisoner of Azkaban” that I actually enjoyed watching.

Be warned, though; if you get the Blu-ray version, you’d best watch it with all the lights off. This is a dark, dark film — Gordon Willis would be jealous of its shadow detail — and the home-video master takes the color timing even further into darkness than the theatrical prints.

Let’s hear it for technological advancement; this would have looked atrocious on VHS.