Born in Rome, Marinelli is the son of actor and voice actor , and the nephew of actress and voice actress . He enrolled at the
Silvio D'Amico National Academy of Dramatic Art, graduating in 2009. Occasionally appearing on stage since 2006, his
breakout role was Mattia, the leading character in the
Saverio Costanzo's 2010 drama film
The Solitude of Prime Numbers. Marinelli also played a supporting role in the Academy Award-winning drama
The Great Beauty by
Paolo Sorrentino. For his role of Cesare in
Claudio Caligari's final film ''
Don't Be Bad'', he won the Pasinetti Award for Best Actor at the
72nd Venice International Film Festival. In 2016 he won the
Nastro d'Argento and
David di Donatello for Best Supporting Actor for
They Call Me Jeeg, and in 2019 he won the
Volpi Cup for Best Actor for his portrayal of the titular character
Martin Eden at the
76th Venice International Film Festival. He also played the antagonist Primo in the 2018 TV series
Trust, and starred as Nicky in the
Netflix film
The Old Guard. In 2018 he portrayed the Italian singer-songwriter
Fabrizio De André in
Fabrizio De André: Principe libero. He starred as
Diabolik in the
2021 film based on the comics series. In 2022, he plays Pietro Guasti in
The Eight Mountains () by Felix Van Groeningen and
Charlotte Vandermeersch, based on
the novel of the same name by
Paolo Cognetti. Marinelli received critical acclaim for his portrayal of
Benito Mussolini in the 2024 series
Mussolini: Son of the Century. In 2025, it was announced that he and his wife,
Alissa Jung, will play the characters Neil and Lucy, respectively, in
Hideo Kojima's 2025 video game
Death Stranding 2: On the Beach. ==Filmography==