Then, Chelli achieved a major fame on stage, starring in a number of successful musical comedies such as Rugantino (1978, together with Enrico Montesano), Cyrano (1979, with Domenico Modugno), and Aggiungi un posto a tavola (1990, with Johnny Dorelli).
In 1962 he played the eponymous character in the musical Rugantino (see also Rugantino in the Italian Wikipedia).
Always in collaboratio with Giovannini, he wrote numerous musicals such as Un paio d'ali, Ciao Rudy, Rugantino, Aggiungi un posto a tavola.
Rugantino is a musical comedy by Pietro Garinei and Sandro Giovannini, which debuted at the Teatro Sistina in Rome, Italy, on 15 December 1962.