A scene in this movie is said to show the first use of a "selfie stick".
David Moore, played by Jirí Sovák, while riding in a carriage, thinks about how he could have killed Hitler through time travel and thus prevented World War II. Ironically, a few years later, in the comedy Tomorrow I'll Wake Up and Scald Myself with Tea (1977), it was Sovák who played the leader of a neo-Nazi group who, through time travel, wants to bring Hitler a state-of-the-art weapon so that he can win World War II. Both films also share screenwriters Milos Macourek and Josef Nesvadba.
At one point of its development, the film was planned as a Czech-Spanish co-production and Spanish singer and actress Marisol was considered for the part of Gwen Williams, eventually played by Jana Brejchová.
Although the whole plot is of course wildly fictional, Albert Einstein's stay in Prague in 1911 is a historical fact.
Some sources incorrectly state that the film is an adaptation of one of Josef Nesvadba's famous science fiction stories from the late 1950s and early 1960s, specifically a story called 'Einstein's Brain'. This is not true. 'Einstein's Brain' is a story about a female scientist who recycles brain tissues from several dead people, puts them into the head of an artificially created human being and calls this invention Einstein's Brain. The subject of the film is in no way related to this story and is a completely original collaborative work by Josef Nesvadba and Milos Macourek.