In 2013, Muschietti directed his debut film, the supernatural horror Mama, which he co-wrote with Neil Cross and his sister Barbara Muschietti.[2][3][4] It was based on Muschietti's three-minute short film Mamá, which attracted Guillermo del Toro, who stated that it had the "scariest" scenes he had "ever seen." The short convinced del Toro to executive produce the feature-length film[5], which starred Jessica Chastain, Nikolaj Coster-Waldau, Megan Charpentier and Isabelle Nelisse, and was released by Universal Pictures on January 18, 2013.[5][6] The film grossed more than $146 million and had a budget of $15 million.[7]