Like many provincial towns, Drossmouth boasts a prolific repertory theatre company. Staging new productions on a weekly basis, the company assemble to rehearse 'Tarnished Gold' a debut play by unknown author, Jeremy St Clair. St Clair is due to attend the rehearsal but the company's producer, Harry Blacker, hates the play and is dreading the author's arrival. He is surprised when the playwright actually arrives because Jeremy St Clair is the pseudonym of Catherine Beckworth, an elderly spinster and aunt of the theatre proprietor.

Tempers start to fray and Avis, a young would-be starlet, has an emotional outburst after receiving a letter from a relative instructing her to return home. Harry thinks Avis is a terrible actress and needs to fire her but, afraid of further upset, ignores her and begins the rehearsal. The play's weaknesses are immediately apparent so Harry sends Catherine away to rewrite the first act.

Norwood Bellamy, the company's star actor, arrives late having been driven to the theatre by an admirer, Sarah Stebbins. Bellamy's wife, Sandra, sees her husband with Sarah and confronts him about his blatant flirting. Their argument is interrupted by an incoming telephone call from Stella Film Productions. Norwood leaves to accept it. Rehearsals continue and Harry despairs at the increasingly dreadful dialogue in 'Tarnished Gold'. Catherine returns with her updated first act, but Harry absent-mindedly discards it. Furious, Catherine phones her nephew to complain about Harry's insolence, but she accidentally intercepts the call from Stella Film Productions.

The company break for lunch and Maude, the matriarch of the company, persuades Avis to give up her dreams of stardom, gently advising that she isn't a very good actress. Avis accepts that she was unlikely to become a star and decides to return to her father. Norwood is disappointed to lose the call from Stella Film Productions and angrily mocks Sandra when she points out that their message could be for her. The film company call again and prove Sandra right. At the same time Mr Stebbings, Sarah's angry husband, arrives unannounced and assaults Norwood. Sandra initially laughs at Norwood's inability to defend himself but, after seeing his embarrassment, comforts him. Norwood encourages Sandra to take the audition offer from Stella Film Productions, saying he will follow her to London.

As the company return from lunch, Harry trips and falls into the orchestra pit. Catherine takes charge and moves him into a dressing room, encouraging the company to continue rehearsing while they wait for a doctor. During the dire rehearsal - attempting to follow the grid-like Meyerhold directing method - Harry appears ghost-like at the back of the theatre and knocks Catherine out with a stage weight.

A week later and the first night is a success. As the company take their final bow, the audience praise the author. Harry happily beckons Catherine to take her applause.