Musicals and horror movies may not go hand in hand — or sequined glove in claw — but one led to the other for Bay Area filmmaker and composer H.P. Mendoza, who went from his career debut, Colma: The Musical, to a series of experimental, experiential, and ethereal films before landing with I Am a Ghost, one of three features Mendoza produced in 2011. Turns out his background in scoring and composing was all building up to this: Real horror — as in suspense over gore, and true scare over mere startle — is all about sound, be it a total lack thereof or a droning, screeching, whining, howling climax. Mendoza brings us into the house and mind of Emily, who's dead and doesn't know it until a medium connects with her inside a Victorian home (in real life, a bed-and-breakfast in the Mission District). Within that house we see the reason Emily's trapped in between — let's just say it ain't pretty. But the film sure is. Menacing, mysterious, and melancholy, I Am a Ghost is arguably the work furthest from the rest of Mendoza's oeuvre, but if every first effort in a genre is this good, we encourage his restlessness.