Sci-Fi & Fantasy series 122 series

A strange premise is the cheapest thing in television. Anyone can split a mind in two, bring the dead home or park a station at the edge of known space; what we score is whether the people inside the idea still behave like people once the novelty has worn off. The good ones use the impossible thing to look harder at grief, work or power. The poor ones spend eight episodes explaining the rules. Our shelf leans towards the 2010s, and towards series that ask for patience: nearly everything we rate highly has a slow first season and a second that repays it.

Start with The Leftovers, 87, hard going at first and then as good as television gets; Severance, 86, for an office built to unsettle; and The Returned, 85, dread without scares in a French mountain town. After those, Star Trek: Deep Space Nine is the Star Trek that grew up, and Over the Garden Wall is done in two hours.