This intriguing sci-fi thriller is a throwback to the kind of cerebral teleplays and low-budget movies that flourished in the 1960s: ripe with gloomy lighting and dystopian pessimism, but with barely enough money in the budget to pay for more than two sets. Think On the Beach from 1959, or Seconds from 1966 – but then lower your expectations because it’s not anywhere in their league. But it’s not bad, and the subject is timely.The time is a couple of decades in the future, and humanity has accepted that we’ve messed up the planet beyond repair. The only answer is to start colonies off-world, starting with the moon. Helping to sow these seeds for the future is an AI called Jay that runs simulations to calculate risks and resolutions. All that is explained in a crawl and with faux news footage. The drama properly begins at a rural house that looks like something from Grand Designs; it’s the home of Jay-creator Sam (Kemi-Bo Jacobs) and astronaut Anderson (Simon Merrells, one of those actors you’re sure you’ve seen before even if you can’t quite place him). He is going to be the head of the next crucial mission to the moon, which launches tomorrow. The couple’s last night together is interrupted by the arrival of Sam’s employee Charlie (Hermione Corfield), who is troubled that Jay’s simulations posit not a trip of a few days but one going to the Jupiter moon Europa, and from there the titular million days journey to Alpha Centauri. Quicker than you can sing “Daisy, Daisy, Give Me Your Answer Do,” the trio start to suspect Jay has gone rogue and has her own agenda.Apart from a few moonlit wanders outside to look for a missing dog, and a flashback to a deep-space mishap rendered with visual effects, everything takes place inside Sam and Anderson’s house. That minimalism is fine, making for an interesting contrast with the vast distances and time spans conjured by the dialogue. But a bit more fluidity and flair in the script would have been welcome, cleaning up the clunky, exposition-heavy lumpiness of it all. A Million Days is on digital platforms on 18 March