[4] In 1988, he debuted as a stage actor in the Greek tragedy La seconda generazione, a collection of pieces by Aeschylus, Sophocles and Euripides directed by Mario Martone.

Starting in 1998 with Più luce non basta directed by Elisabetta Lodoli, Ragno has played various roles in different television productions, establishing himself as the protagonist in the series Distretto di polizia and Il tredicesimo apostolo.

Since 2004 he has been narrating literary classics such as The Picture of Dorian Gray, Dracula, A Room with a View and Frankenstein on the program Ad alta voce on Rai Radio 3.

[12] For his role of Marcello in the 2018 series Il miracolo, directed by Niccolò Ammaniti, he won the Flaiano Prize as well as the Golden Screen Award.

In 2020, he played the Italian mafia boss Donatello Fadda in the fourth season of Fargo, written and directed by Noah Hawley.