Presenting new vein of terror in familiar haunts of Eastern State Penitentiary

It’s not even October yet, but Halloween season is already starting.

This weekend, the historic Eastern State Penitentiary in Philadelphia’s Fairmount neighborhood will begin its 27th annual fright fest, “Terror Behind the Walls.”

Every year, the staff of the former prison tinker with the “Terror” concept to make it as attractive as possible for Halloween audiences hungry for ghouls — without marring the year-round educational mission of the historic site and museum .

Fabricating horrors that are less focused on the prison experience — while still making the creepy old prison as scary as possible — requires a certain finesse.

This year, Eastern State Penitentiary introduces Blood Yard, wherein a colony of post-apocalyptic barbarians camp in the prison’s former exercise yard.

“You see what resources they have scavenged from around the prison,” said artistic director Amy Hollaman. “There’s a story that they have run out of food, so they have used the only other resources they have — which is each other. They have started to eat human flesh.”

“Terror Behind the Walls” is, ultimately, a fundraiser that generates two-thirds of Eastern State Penitentiary’s annual operating budget. The Halloween frights provided half of the funding for “Prisons Today,” a recent award-winning exhibition outlining the problems of America’s criminal justice system.