Spaceplane "Three G. » flew to explore the planet Troy in the system of the double star Lagrange, where every single settler died from an unknown epidemic On board the flying ship were scientists, researchers, instruments, and Mark Annuncio, a pupil of the Mnemonic Service. The students of this organization were engaged and brought up by one thing - to remember everything .. Why? The fact is that each specialist knew only his field of knowledge, in the other he was full of profane . To compare the facts from different industries, such a scientist was no longer able to . That's why we needed Mark on the ship .. His task was to collect all the information and compare them, because the computer can not freely analyze any facts and he lacks such a thing as intuition.