Le Grand Œuvre, Le Voyage Alchimique, is an initiatory and spiritual quest that twins, Adam and Galahad Magritte, illusionists by trade, will undertake in order to transmute their feelings of lead into gold. During one of their shows, they will find themselves propelled into a mystical world, an intermediate dimension, which will never cease to surprise and challenge their minds. There, they also befriend some amazing characters, including a ghost, Victor and his raven. With the help of their guides, Adam and Galahad will penetrate the meanders of their being by crossing, according to the alchemical model, the black work, the white work and the red work. The twins will travel through time and space, welcoming each trial and each teaching offered to them, to fight against frightening dark and destructive masses.