When an incorrect diagnosis of Lister’s chest pains reveals that the system software on Red Dwarf hasn’t been updated for some time, the crew find that the required upgrade isn’t quite what they had in mind.

Like last week’s Mechocracy, there’s a lot going on in this episode. An awful lot. Unlike some half-hours where the high concept is established in the opening minutes, the story is still rapidly unfolding at the half-way point. Too many ideas? Maybe. It’s like the floodgates have opened and Doug Naylor is just pouring out observation after observation, wryly commenting on everything from mobile phone and satellite packages, security questions, trying to revert to previous versions of software, backing things up – it’s non-stop.

The conceit of Lister being alone on the ship, his crew mates starting to disappear, isn’t a new one (mined memorably in Star Trek’s The Mark of Gideon, The Twilight Zone’s And When the Sky Was Opened) but before it feels too familiar we’ve moved on to the next set-up or barbed comment on consumerism.

Verdict: Perception filters, software upgrades, the Earth being bought by a mega-corporation – they even bought the bad things: the maggots, quicksand and American chocolate! Fast, fun, inventive, and ending in such a way that surely a big reset switch is needed, this series just gets better. 9/10

Nick Joy