A shocking scene of filth and depravity was uncovered in a quiet California neighborhood — where a dozen emaciated siblings were found shackled to their beds with chains and padlocks after a 13th managed to escape the nightmare, police said Monday.

The siblings — ranging in age from 2 to 29 — were allegedly being held captive by their parents inside a Perris, Calif., home, about 70 miles east of Los Angeles, the Riverside County Sheriff’s Department said.

The discovery was made after a 17-year-old girl escaped from the hell house on Sunday morning and called cops on a cellphone she managed to sneak out with her.

Police soon located the teen, who they said looked emaciated and appeared to be about 10 years old, the network said. The girl then told officers about her 12 siblings shackled inside the home.

Cops found five children inside the home malnourished, unwashed and shackled with chains and padlocks. Seven more captives were adults — ages 18 to 29 — but appeared young due to malnutrition.

Once freed from captivity, the siblings said they were “starving,” according to the Los Angeles Times, and were given food before being taken to the hospital.

Parents David Allen Turpin, 57, and Louise Anna Turpin, 49, were taken into custody for the nightmarish conditions inside their home.

“The parents were unable to immediately provide a logical reason why their children were restrained in that manner,” the sheriff’s department said in a statement.

Public records show the couple filed for bankruptcy in 2011. David listed his employer as defense contractor Northrop Grumman.

David’s mother, Betty Turpin, told The Post she was surprised by the allegations and called her son a “very good man.”

“He is very protective of the kids,” she said. “Everything is always in order.”

The grandmother said she hadn’t seen her grandchildren in a few years because they lived too far away.

Neighbors were appalled to hear about the house of horrors just down the block.

“It’s crazy. I was shocked,” one neighbor said. “We used to walk by there all the time.”

They described the family as recluses and described the home as desolate.

“My kids tried to sell them candy,” Antrina Mojica told The Post.

“They could hear people inside but they wouldn’t open the door.”

Mojica said the children at the house rarely came outside and would stay on their front lawn.

“My kids would walk by there all the time,” she said.

“They knew that there were kids in there. There would always be packages on the porch.”

Another neighbor said he witnessed a few “dirty” kids out on the lawn while there was work being done.

“I saw two or three kids once,” the neighbor said. “They looked dirty. They were doing the front yard . . . I just thought they were dirty from working.”

He said the lawn had weeds about 4 feet high before the summer.

“It’s a very quiet house,” he said. “It looked like it was abandoned, like no one lives there.”

The lawn had apparently been cut after a visit from local officials to enforce an ordinance for an unkempt yard.

The home is listed in state records as the Sandcastle Day School, with David as the principal.

The parents had renewed their marital vows in Las Vegas three times since 2011, said Kent Ripley, an Elvis impersonator who officiated at each ceremony. They brought their kids along twice.

“The only thing that seemed peculiar was the size of the family,” Ripley said. “I mean that’s the Brady Bunch times two plus one. But they all seemed polite, not rude and not underfed.

“They said they cared about each other. They thought this [exchanging vows] was a good thing and wanted to include their children.

“As soon as I saw their pictures [on the TV news], I was sick to my stomach. It’s so shocking.”

The couple was being held Monday night on suspicion of torture and child endangerment. Bail was set at $9 million each.

Additional reporting by David K. Li