A year after her death sentence, Elena is given a choice between the gallows and the position of commander Ixia's personal taster. The girl will have to determine the presence of poison in the commander’s food, for which she must not only learn the names, but also be able to distinguish 152 types of poisons by taste, smell and aftertaste. In addition to convulsions, hallucinations and nausea - the usual consequences of the poisons being studied - Elena receives a “baptism of fire” in the form of a lethal dose of the Butterfly Pollen poison, which tied her to the castle walls with invisible bonds. Her future is bleak, and death guards around every turn. But Elena survives the test of poison and unexpectedly finds herself involved in a cycle of political intrigue, finds true friends and first love.