‘They have found massive weapons of destruction capable of being deployed within 45 seconds.’ This is clearly political, albeit picking an easy target of the unpopular Iraq War, then two years in. There are (non-existent) massive weapons of destruction; the Blairite Prime Minister gets killed and shoved, unmourned, in a cupboard, and Harriet Jones MP declares, ‘I voted against that.’ Implausibly, it turns out the UK has abdicated operational independence of its nuclear weapons to the UN (which makes no sense given a second’s thought), and so the Slitheen have had to manufacture an alien invasion crisis to convince the UN to pass a resolution. This is an incredibly awkward stretch just to make the allegory work. The other unfortunate bit of plot expediency is the Doctor having an all-access password that allows him to take control of the Royal Navy. The show frequently seems to pluck endings out of the air, but this particularly takes the biscuit.

Your tolerance of this depends on whether you can overlook these issues. Personally, I think this absolutely fizzes with energy and excitement, a writer who’s finally got the trip of a lifetime and intends to make the most of it. After the UNIT thriller aspects of the first episode this flips into base under siege mode, with the Doctor, Rose and Harriet largely stuck in one room, forced to rely on Mickey the idiot to save the world. The scenes inside the Cabinet Room are extraordinary: just three good actors playing the shifts in power as the Doctor brilliantly ‘narrows it down’ to identify the weakness of the Slitheen, and – from miles across London – save Mickey and Jackie. But he’s clearly dwelling on Jackie’s question: ‘Is my daughter safe?’, unable to make a decision that could save the world but kill Rose (another strength: the stakes are very clearly articulated) until Harriet Jones finally shows her mettle and commands him to do it, and Rose comes up with a way for them all to live.

Eccleston is brilliant in this, his first recorded story: the little smug smile he gives to the Slitheen as he vanishes in the lift; the petrifying glare he turns on Margaret Blaine (his brief face-off with Annette Badland is so good it’s a no-brainer they needed to bring her back for a proper showdown); his discomfort as Jackie questions his lifestyle, and the panic on his face at the end as Rose and Jackie hug and he scurries inside the TARDIS. But I think all the regular cast work better here than in Rose: Camille Coduri strikes the balance between Jackie’s comedy misunderstanding (‘Slickeen!’) and genuine distress for her daughter (notably, she’s not at all reconciled to the Doctor by the end). Noel Clarke is less cartoonish as Mickey, who proves his worth and gets to be the second person (after Grace) to turn down the chance to be a companion.

On the other hand, the Slitheen aren’t as impressive as in Aliens of London. The marry-up between the swift and sleek (but lacking in detail) CGI versions and the bobbling costumes just doesn’t work; it would have been better to pick one or the other because the chase scenes flip from a computer Slitheen moving like a hunter across the frame to one swaying about comically in close up. The show generally gets better at this and Series One, like the first Hartnell season, is a learning curve, testing approaches that – for better or worse – don’t crop up again.

A lot of the child-friendly comedy in this will, like the Slitheen in later seasons, get hived off into The Sarah Jane Adventures: a smart move, as kids that started watching in 2005 got to grow up as the show did, and a new audience had a reception class on CBBC (moody teenagers got Torchwood). I don’t think Aliens of London/World War Three entirely works, but I didn’t think The Pirate Planet did either and it’s still one of the classics. We shall not see its like again.

Next Time: Dalek