Rosemary and Thyme (2003)

Rosemary is delighted to be working on the garden of an open-air theatre with Laura, as her cousin Charles is an actor preparing for his role in an amateur production. But during rehearsals, one of the actors is suddenly killed by a prop gun, which police discover had been loaded with live ammo instead of blanks. The two gardeners soon wonder if someone is out to sabotage the play, or whether there is another motive at work...