The plot takes place in 1925. One of Chicago mobsters Mik Nich (born as Mikita Nechyporuk) flees to Soviet Odessa to escape the revenge of other mobsters. Mob leaders send the best hit-man Johnny Pollack to Odessa. The killer disguises himself as an American entomology professor Pollack, which wants to visit the grave of his father in Odessa. In search of his victim, Pollack gets the most unbelievable situations arising from the peculiarities of the city of Odessa, as well as from mad historical era. Because he is the first passenger of the ship voyage New York-Odessa, he is assigned to be accompanied by the Komsomol guide Glushko and is besieged by pioneers and journalists. Jumping from the train and hitting his head, Pollack forgets what he is actually doing there (retrograde amnesia), and tries to live up to its cover as an honest professor. Nechyporuk in its turn experiences about the arrival of the killer and is trying to kill him. Pollack is passing periods of regain and loss of memory (a periodical Déjà vu) while trying to track down Nechyporuk.