The book “Accidents are not accidental” opens the series “Call Sign “Swallow”” about the fate of a married couple of Soviet illegal intelligence officers. Covers the period 1935-1959. Victor and Taisiya were very young, almost children, when this life-long story began. They met by chance and fell in love with a friend of a friend. They believed in a lucky star, and fate united them. The soldiers of the invisible front are illegal intelligence officers, always on the front line. Far from the Motherland, its borders are guarded. Their exploits are classified. Agent pseudonyms keep secrets. If they fail, they face arrest, interrogation with violence, and execution without publicity. If you're lucky, an exchange. They are where they are not. They are not there, but they are here.