In 1940, he arrived in Rio de Janeiro, "with four changes of clothing and five quid in the pocket", to work as a sports commentator for Radio Ipanema.
His family now increased by a son and daughter, Rita and Antônio Maria Filho, he took a position as Rádio Tupi's production director, and was also a feature writer for the "O Jornal" newspaper.
In his Cop's Story column, Antônio Maria would frequently interview the protagonists of the moment, right in the police stations and on the streets of Copacabana or in the middle of the night.
In 1952, two of his works: "Menino Grande" and "Ninguém Me Ama", were Top Ten hits on the Brazilian radio.
In 1959, in partnership with Luiz Bonfá, he composed the incomparable hits: "Manhã de Carnaval" and "Samba do Orfeu".