“Holiday in the Hills,” opening Friday, is a musical is set in Folsom in the late 1880s narrated by Peter Hopper, then-editor of the Folsom Telegraph. According to Mike Jimena, characters in the play are based on historic residents of Folsom. The show has become a regular tradition in Folsom, showcasing dozens of actors. The show is original, with some story changes every year to keep things fresh, according to Jimena. “It’s a quality production,” said Jimena, who owns Stage Nine with Mockenhaupt. “That’s what we’re known for.” Stage Nine Theatre/Garbeau’s is the area’s only full time theater.