Disturbing new details in the case of a Chinese-American couple accused of farming 21 children inside their Southern California mansion were revealed in court on Friday.

Guojun Xuan, 66, and Silvia Zhang, 39, are accused of keeping a “house of horrors” at their $4 million Arcadia mansion, where prosecutors allege child abuse stemming from their mass surrogacy operation.

At a bail hearing on Friday, Los Angeles County Deputy District Attorney MacKenzie Teymouri said the couple hid the nearly two dozen children from the world, restricting them from ever seeing sunlight, according to the Los Angeles Times.

“They didn’t go to school outside the home. They didn’t go to playgrounds. They didn’t go to restaurants,” Teymouri said. “They lived in this home and witnessed violence in the kitchen, in the bathrooms, in the bedrooms, in the foyer.”

Cops also found the cremated remains of a surrogate child that had been sent to the house after the baby died in Florida, Teymouri added. She said the pair never opened the box and appeared to be “indifferent” to the fate of their children, the Times reported.

The children were expected to work nearly 24/7, learning “math, Mandarin and English,” prosecutors said. They were also allegedly ordered to sit up straight and listen or suffer beatings.

The children sat in “makeshift classrooms” from the dawn till dusk, prosecutors said.

“From sunup, to sundown, these children, whether they’re in a high chair or old enough to sit at a desk, sat in what can only be described as makeshift classrooms,” Teymouri said, according to the Times.

The children stayed indoors for so long that when the Department of Children and Family Services took them into custody last year, they were “scared to go to the park because they hadn’t been outside,” Teymouri added.

Prosecutors obtained video of Xuan sweeping a flashlight through the beds of sleeping children and would beat any child that was awake. Teymouri also noted she needed to mute video footage she reviewed due to the “constant screaming” of children in the background as a result of the persistent beatings.

Xuan has been charged with conspiracy to commit a crime, child abuse and accessory after the fact, along with five counts of dissuading a witness.

Zhang was charged with conspiracy to commit a crime and accessory after the fact, along with four counts of dissuading a witness.

Los Angeles County Superior Court Judge Caroline Lugo held the couple in lieu of $20 million bail, concurring with the prosecutors that they were a flight risk.

Teymouri revealed their nanny, Chunmei Li, fled to China with the couple’s help. Li had been charged with child abuse for hitting a child so hard they required hospitalization for brain bleeding.

Mitchell Krems, Xuan’s attorney, said his client had never been convicted of a crime, blamed the abuse on nannies, and said the couple are victims of anti-Chinese sentiment in the US.

He also argued his client should be freed because of his deteriorating condition in police custody because of leukemia treatments that have contributed to him being permanently bound to a wheelchair.

Zhang’s attorney argued that the expensive bail was unncessary, citing the children’s luxury accommodations.

“These kids, there was no cigarette burn marks. There was no cages. There was no dog collars. There was no abuse by belts. These kids were well nutritioned, they were getting education every day,” he said.