Jan Švankmajer at 85 years of age is one of the most prominent artists of European cinema. His work has inspired and guided generations of directors, and his work represents a sharp and merciless exploration of human nature which is entirely unique. When Švankmajer decided to stop filming after Insect (2018), his producer suggested that the creative processes which ferment within their film company Athanor should be preserved on film. Over three years, the directors followed the life of Jan Švankmajer, elucidating his artistic principles, as well as his collaboration with old friend and producer Jaromír Kallista. The film is also haunted by the memory of Eva Švankmajerová, his wife and creative partner, muse and inseparable other half. Alchemical Furnace is shot on various film formats in combination with found footage. Playful and poetic, candid and with a touch of Czech humour, it is an ode to creation and to companionship.