(CNN) In a vivid new description of ISIS' brutal executioner, a former hostage says his captor was not only sadistic, but bizarre.

Daniel Rye, a 26-year-old photographer from Denmark who was held captive in Syria for more than a year, said that one of his jailers was the hooded figure in black who spoke in ISIS execution videos

In an interview this week, Rye described an encounter with the man, who has been nicknamed "Jihadi John" by the British tabloids.

"He picked me up and I had to dance the tango, John and I," Rye told Danish broadcaster DR. "My head was down and afraid of being beaten. He led me around the prison. Suddenly, he changed and just pushed me down. They kicked and hit me. They finished by threatening to cut my nose off with pliers and things like that."

Michael Weiss, co-author of "ISIS: Inside the Army of Terror," said Emwazi displayed an "almost '(A) Clockwork Orange' sense of sinister humor about torturing."

"It's just another addition to the sick and twisted annals of the way ISIS treats human beings," he said.

Former CIA analyst Aki Peritz says it is likely that Emwazi, like many ISIS recruits, is drawn to the grotesque.

"The guys who run this organization, a lot of these guys who control their hostages, they're sadists," he said.

Weiss said that online supporters of ISIS have reacted with glee to the story of the tango. Fairly or unfairly, he said, supporters of ISIS are trying to draw a moral equivalence between the mistreatment of jihadi suspects by American interrogators and the mistreatment of kidnapped Westerners by ISIS -- from the orange jumpsuits to the forced stress positions.

Photos: Documents show how ISIS functions as a government Photos: Documents show how ISIS functions as a government This birth certificate from the Halab Health Department records information for babies born in the ISIS-created province or "wilayat." Hide Caption 1 of 7 Photos: Documents show how ISIS functions as a government Mothers are reminded how important children are to God and are then instructed to follow a vaccination timetable against polio, measles and other ailments. Hide Caption 2 of 7 Photos: Documents show how ISIS functions as a government This notice declares that the University of Mosul will open on October 18, 2014, but that the philosophy and archeology departments, among others, will remain closed. Staff are told to replace all mentions of the "Republic of Iraq" with "Islamic State." Hide Caption 3 of 7 Photos: Documents show how ISIS functions as a government A schedule for final exams at the Mosul College of Medicine shows areas to be tested included students' knowledge of obstetrics, parasites, X-rays and ethics. Hide Caption 4 of 7 Photos: Documents show how ISIS functions as a government This notice criticizes the greed of some fishermen and lays out new rules, including no fishing during spawning season and no use of electrical current to catch fish, as it harms other creatures, too. Hide Caption 5 of 7 Photos: Documents show how ISIS functions as a government This document poses a question on playing foosball. Readers are told that it's OK, provided that there is no gambling, no cursing or resentment and that the figurines have no heads. Hide Caption 6 of 7 Photos: Documents show how ISIS functions as a government This message quotes the Quran, and speaks in favor of charity and helping those in need. It then details how rents above 100,000 dinars (about $85) must be cut. Hide Caption 7 of 7

Emwazi has not appeared in a beheading video since January, and Weiss said it is unclear whether he is even still in Syria.

"His status has actually taken a beating in the last few months, since he's been outed," Weiss said. "He has apparently fled. So he's not quite the celebrity and the spokesman that he used to be."

One possible explanation, Peritz says: ISIS might be running low on Western hostages to murder.

But Peritz warns, that does not mean that Emwazi is no longer a threat. "If there's another Western hostage," he said, "you better believe that he's going to be in that video."

Rye was held hostage in Syria from May 2013 until June of 2014, sometimes with other foreign prisoners including American James Foley . He told the Danish newspaper Berlingske that Foley stood out as a warm and righteous man, even in captivity, where there were fights about food, and aggression was often just below the surface.

Rye said he committed to memory a final letter from Foley, and conveyed it to Foley's family soon after he was freed.

"It was terrible. It was a death letter, a farewell to his family," he told Berlingske. "If I were to think of the letter every day, then I would be a wreck today."

Rye was released, reportedly for a large ransom paid by his family, two months before Foley's beheading was shown in the first of a series of gruesome ISIS videos.