The First Men in the Moon, BBC Four

Obviously the world has decided it needs Mark Gatiss, and it keeps finding things for him to do. An influential figure in the latterday revival of Doctor Who, as well as co-creator of the BBC's recent Sherlock, Gatiss's forte is turning out to be whimsical old-fashioned adventure stories, perhaps overlaid with a patina of science fiction.

In that case, what could be more appropriate than an update of H G Wells's novel The First Men in the Moon, originally published in 1901? The protagonist, the charmingly eccentric scientist and inventor Professor Arthur Cavor, could have been the Doctor Who of his era, with his enlightened views on progress and social harmony. The book's message about the evils of imperialist adventurism isn't really necessary in today's defence-cuts Britain, where it's beginning to look as if we'd struggle to mount a seaborne assault on the Beachy Head lighthouse. It's an enduringly fashionable viewpoint, nonetheless.

Once more, the Stakhanovite Gatiss led from the front, writing the script as well as taking the role of Cavor. Alongside him was Rory Kinnear - steadily morphing into the spitting image of his dad Roy - as Julius Bedford, a disreputable chancer ruined in a bad business deal and now scuffling around for any opportunity to make a fast buck. Having down-sized to a homely country cottage while trying to write a play, he found himself disturbed by the nutty Professor wandering past his front gate making peculiar absent-minded noises (Mark Gatiss and Rory Kinnear, pictured below).

Long story short? The Prof has invented a gravity-defying substance called Cavorite, gets talked into partnering-up with Bedford who can't believe the money-making potential he has stumbled across, and develops a plan for travelling to the Moon in a Cavorite-powered module. Once you switch on the power, the Cavorite does its stuff and the little craft (a veritable proto-TARDIS) whizzes off into space.

The First Men... was all about tone and underlying philosophy rather than cutting-edge sci-fi. Apart from anything else, Wells's story was ridiculous, positing a Moon with a breathable atmosphere, peopled by green beings who looked (as Bedford put it) like ants walking on their hind legs and who had developed a strange underground civilisation. Bedford's eyes lit up when they found lumps of gold scattered around the landscape, and seams of gold running through the rock strata. The Grand Lunar, who ran the place, looked like a big dollop of seaweed hanging from the rafters.

But the joy of the piece was its gentle, thoughtful tone, perfectly embodied by Gatiss as the Professor, whose sole ambition before he met Bedford had been to be elected a member of the Royal Society, that exemplary home of the gentleman-adventurer. His finest moment was his wistful reverie about how, if they were only able to remain long enough on the Moon, they would discover a wise and sophisticated civilisation who had built great underground cities, perhaps bordered by a mighty subterranean lake.

But Bedford had set the cat among the pigeons by killing a couple of their lunar captors, causing Cavor to foresee only interstellar colonisation, greed and war. The Prof's ultimate self-sacrifice to prevent interplanetary war did have the regrettable downside of wiping out all life on the Moon, but he meant well.

In rewriting the story, Gatiss had invented a new framework in which the 90-year-old Bedford told his tall tale to a young boy, on the day in 1969 when Neil Armstrong was about to take that small step, and giant leap, onto the lunar surface. A cute idea but an unnecessary one, since all it achieved was to throw in an extraneous layer of period recreation. On the bright side, there must be loads more of this sort of stuff that Gatiss could turn his hand to.