In 1993, Grosso's monologue ''Mama Don't'' was produced by the
Royal Court Young People's Theatre and put on at the
Commonwealth Institute, London. It was directed by Roxanna Silbert. A year later, his first stage play,
Peaches, was produced by the Royal Court Theatre in association with the
Royal National Theatre Studio and put on at the Royal Court Theatre, London. It starred
Ben Chaplin. According to
Michael Billington, the season in which
Peaches appeared (which also included
Blasted by
Sarah Kane) defined the historical importance of the Theatre Upstairs, a season of new writing masterminded by
Stephen Daldry. In 1996, Grosso's second stage play,
Sweetheart, was produced by the Royal Court Theatre and put on at the Royal Court Theatre, London, before embarking on a regional tour. It starred
Kate Beckinsale. In 1998, Grosso's third stage play,
Real Classy Affair, was produced by the Royal Court Theatre and put on at the
Ambassadors Theatre, London. It starred
Joseph Fiennes and
Nick Moran. In 2000,
Matthew Rhys played the lead role in
Peaches, the film of the play written, it was also directed by Grosso. His fourth stage play,
Kosher Harry, was produced by the Royal Court Theatre and put on at the Royal Court Theatre, London, in 2002. It was directed by
Kathy Burke and starred
Martin Freeman. The same year, Grosso was invited to participate in the inaugural 24 Hour Plays at the
Old Vic Theatre, London, hosted by artistic director
Kevin Spacey. Grosso's plays have received further productions in theatres such as the
Salisbury Playhouse, other European countries, and American cities including New York, Chicago, and Los Angeles.{{cite web |url=http://theater.nytimes.com/2007/10/22/theater/reviews/22kosh.html ==Critical response==