Based on real events, A Day in March tells the true story of Ettore Majorana, widely considered one of the geniuses of modern science. Majorana contributed to the research that would eventually lead to the creation of the Atomic Bomb. Ridden by guilt, and anguished by the pressures of Mussolini's Italy, Majorana took the most drastic step of all: he faked his own death. The screenplay recounts his life leading up to his disappearance, and then branches out into 3 different scenarios of the lives he might have led after disappearing. The story is framed by journalist Bruno Conti's assignment, 15 years after Majorana's "death", to finally put an end to speculation and solve the Majorana case.