If you transcribed the narrator’s script in almost any episode of Horizon, you’d notice something striking: an awful lot of the phrases would end with a colon, and for one obvious reason: to play a neat trick on the viewers: that of making them keen to hear what comes next. (You get the idea.) Monday’s programme therefore began by explaining that the mosquito is ‘the target of one of medical science’s greatest quests: the battle to save millions of lives and end a scourge that has shaped human history: malaria’.

Unusually for an uncompromising science documentary, the finale was a genuine tear-jerker

Now in its 51st year, Horizon has spent at least the last ten of them often trying too hard to reassure us that science isn’t boring (no, honestly, please don’t switch channels). But with The Battle to Beat Malaria it was back to its old-school best – telling a complicated story clearly and authoritatively; structured in such a way as to provide real narrative thrust; and above all, relying on the material itself, rather than a hyperbolic voice-over, to supply the excitement.

Even that dramatic introduction, for example, was no exaggeration. Despite our fear of them, sharks kill around ten people annually; mosquitos........

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