For sci-fi fans who prefer their adventures on-demand in high-def comes this latest installment from the BBC’s Dr. Who spinoff. The show about a team of alien investigators who battle a constant threat of invasion, Torchwood is a mature and dark series within the genre. This five-part miniseries, which aired in America last July, puts the battered team on the wrong side of the law with the government pursuing them while the children of Earth are attacked by extraterrestrials. This is a mythology-heavy set, but still easily digestible by new and established fans of the show.