If adapting the story of Count Dracula for the stage is a tricky task, then adapting it as a musical must be really challenging. But Piedmont Oakland Repertory has met this challenge with Blood Tango, an original musical adaptation of the Dracula story first popularized by Bram Stoker’s 1897 novel and immortalized in various adaptations for the stage and screen in the decades since. Opening on February 13 at the Pacific Boychoir Academy (215 Ridgeway Ave., Oakland), the play will run through March 13. Blood Tango was written by Piedmont Oakland Repertory producer and artistic director John McMullen, who was joined by composer and pianist Tal Ariel and actress and singer Elizabeth Jane Dunne in composing the musical’s score, which includes fifteen original numbers. Set in an asylum on the English coast in 1922, Blood Tango borrows some of its character names and broad plot points from Stoker’s novel, but as its title may suggest, reimagines them in light of a certain craving not for blood, but for a dance craze nearly as dangerous: the tango.