Act I

The play begins during the final dress rehearsal at the Grand Theatre, Weston-Super-Mare for the regional tour of the new British farce Nothing On. It is late at night and the play is supposed to open tomorrow. Tensions are running high as the director, Lloyd Dallas, struggles with the cast, who are tired and frustrated. The play itself is not very good, a formulaic farce involving tax evasion, a Sheikh, and various plates of sardines. Among the many problems being faced by the company; Leading Actress, Dotty Otley, appears to have forgotten all of her blocking. The alcoholic Selsdon Mowbray keeps disappearing, Frederick Fellowes wife left him this morning, and Brooke Ashton keeps losing her contact lenses. To make matters worse, Lloyd is having an affair with Brooke and the inexperienced assistant stage manager, Poppy. As the rehearsal continues, more revelations and dilemmas come to light, leading to tears, arguments, sickness and nosebleeds, before they finally reach the end of their Act I run-through.

ACT II

Act II takes place one month later when Nothing On is open and running. The cast are about to perform a matinee at the Theatre Royal. This time the action takes place backstage before and during the performance. The cracks that were beginning to show in Act I have grown larger and the relationships within the company have become more complicated and are rapidly deteriorating. Dotty and Garry have locked themselves in their respective dressing rooms after an argument. Lloyd sneaks backstage to see Brooke, which just makes thing worse. When the performance starts, the backstage actions continue as a dumb-show with the actors struggling to deal with another disappearance by Selsdon, Garry's jealousy of Freddie, and Brooke's threats to walk out of the show. As props are misplaced, entrances are missed, and pranks are played, the performance descends into chaos and Act I ends with Poppy loudly revealing to Lloyd that she is pregnant with his baby.

Act III

Nothing On is wrapping up its 10-week tour and about to perform at the Municipal Theatre. Tim announces that the show will be slightly delayed, as we hear Doty and Belinda screaming at each other backstage. When the show begins, Dotty is limping and distracted, getting lines and blocking completely wrong. Things go from bad to worse as the action continues, with the actors changing the play considerably, making mistakes, trying to cover them up, and making things worse. With Lloyd's guidance, the cast manages to stumble towards a vaguely happy ending.