If you liked the X-Files then there's a very strong chance that you'll like Dark Skies. It's clearly highly influenced by the X-Files, and unashamedly so, even down to the similar music. In many ways it feels like it could have been a spin-off prequel with its heavy focus on conspiracies surrounding key moments in American political history - ie the Kennedy assassination. At times it tries a bit too hard to weave in reports, stories and figures from science and UFO lore including, for example, Dr Carl Sagan who appears in a few episodes without really contributing to the development of the drama.
For some reason the 90-minute pilot episode - directed by horror veteran Tobe Hooper - is not on disc 1 but on the final disc. Episode 1 on disc 1 is a sort-of secondary pilot (it is fairly common that TV series are re-tooled after the initial pilot) but does not give sufficient background detail as to what is motivating the lead characters to do what they are doing. Throughout the episodes, references are constantly made to events that are in the 90-minute pilot which, having now watched it after the whole series, suddenly makes alot more sense..!