The countries of _______land and _________ia have a tense, glacial relationship: while not at war, diplomatic relations are strained, and public expressions of frosty goodwill are belied by the covert jockeying for advantage between respective espionage agencies. The two are not equal, however: where ___land is a free and open democracy, proud of its moral and military superiority, ____ia is a police state whose borders permit only a few privileged or innocuous individuals to pass in or out, whose citizens can neither trade nor travel freely,where every telephone conversation is accompanied by the silence of another listener, and strangers are feared and mistrusted.

Despite the differences between them, there are still things that are prized by both sides, of course: money, influence, knowledge. It was in pursuit of this last item that agents from ___ia kidnapped a woman known only to you by her codename, the Princess. A brilliant young scientist, her work on macro-scale harmonic resonance led directly to the formation of the elite group of which you are a member. As the government of ___ia have long suspected (but your own has never confirmed), her work is more than purely theoretical — using the discoveries of her and her team, the covert agency to which you belong have developed ways of creating and manipulating special frequencies, frequencies which can be combined together to cause sympathetic vibrations in objects that cause them to move, to change shape, even to shatter.

This last ability is going to prove crucial if she is to be brought back to the safety and protection of ___land. Cruelly imprisoned in a subterranean dungeon, guarded day and night by crack troops sworn to uphold the glory of ___ia, her rescue would still be a straightforward matter for the special forces of ___land, were it not for the cage of solid crystal that surrounds her. If this were broken, our special forces would make short work of the guards and bring her safely home in the time it takes to raise a flag and sing a verse of the national anthem. But the crystal is impervious to all common tools of destruction. The cage’s makers laugh at sledgehammers and chisels, at diamond drill bits and laser technology: the weapon has not been made, they believe, that will release their prize. Such is their confidence that a mood of complacency is even rumoured to have infected the shock squadrons manning her gaol.

Their confidence is misplaced. The agency of which you are a member has the skill and knowledge necessary to shatter the crystal into a thousand impotent shards. All that is needed is for the members of your cadre to align themselves in the appropriate geometric figure for the frequencies you generate thus to sing in harmony with the molecular structure of the crystal cage and so break it into tiny pieces. Your vital mission is to journey to ___ia, arrange yourselves in the pattern designed by the boffins in the back room, and show the Princess that her work has reached its full potential: after which, of course, the heavy mob move in and it’s back to the old country for tea and medals.

Things being what they are, diplomatically speaking, getting into ___ia isn’t as straightforward as it might be, and your team have had to use the only channels available to them. At the time of writing, the only way to travel between the two countries is as part of some sort of cultural exchange programme. You, and the rest of your team, are all going to ____ia on a bird-watching visa, and at your every waking moment will be accompanied by a team of ‘cultural advisors’ intent on steering you towards the rarest and most sought-after specimens.

Make no mistake: this is a tricky business. How are your team going to find sufficient time to align yourselves in the necessary fashion without alerting your hosts to the fact that you may be more than simple ornithologists? Will your minders realise your intent, and double their efforts to make you stand where you don’t wish to stand? And — perhaps most perturbing of all — can the human brain withstand the frequencies needed to see this mad caper to its conclusion?