For my money only three series in the history of television can be called masterpieces — The Twilight Zone, Upstairs, Downstairs and Breaking Bad.
The Twilight Zone, being an anthology show, is the most uneven of the three, with many different writers and directors and actors contributing content over the run of the series. It featured several types of genres, from sci-fi to the supernatural. Even so, the quality of the work is consistently high, and quite often brilliant.
Almost all of the episodes, of whatever genre, deal with subterranean modern anxieties, centering on the themes of personal isolation and the inherent, bewildering threats of advancing technology — themes that continue to haunt contemporary life. These themes give the series a rough sort of coherence and an enduring relevance.
You can buy the whole series in a wonderful new Blu-ray edition, packed with supplements. It belongs in every civilized home.