This has a professor solving the Riemann hypothesis. An race of aliens sees (somehow) that this has happened, and one of the aliens is dispatched to earth to dispose of the professor and anyone else who knows about his work.
This was one that was recommended by A Good Read and sounded promising but it was a bit of a let-down. A bit like Resistance is Futile, the alien disguises himself as a human, and although it's not as bad as that book, he tries for comic effect in the same way: his alien character is frequently bemused by certain aspects of human life and describes them in a very literal way which makes them sound silly.
But the character isn't always ignorant of idiom etc. - only when it's "funny". For example, at one stage someone asks him if he's been under pressure lately, and he wonders "air pressure? Gravity? of course I've been under pressure!". But a couple of pages later he describes someone as looking as if she's "stressed out". And he describes a boy "putting a rolled up tube in his mouth and then lighting it", where I think he'd be more likely to say "trying to set it on fire" if he really had no idea what he was watching.
Needless to say, and like the other book, this alien ends up deciding that humans are OK after all, and it's wrong to fulfil his mission, and that he wants to become fully human. Predictable.
The one thing I did think was good is that he never explains why it's important to make sure that humans don't realise that the Riemann hypothesis is solvable. I half-expected some half-cocked explanation of why this would lead to the secret of FTL travel or something, but it remained mysterious. Although, if I were being uncharitable, I'd say that it's only because the author couldn't think of a good way to explain its importance.
Completed : 31-May-2017