Finding a first edition copy of James Hilton's Lost Horizon was a big score for Luuk deVries, a book collector from Breda, Netherlands, but what he found tucked inside the book absolutely blew him away: the answer to a 75-year-old mystery.

Tucked between the pages of the book, which tells of a man who finds a mythical city in Tibet, was a letter.

"The paper looked old, I thought 'this is probably just a note wishing someone a Happy Birthday or something'," deVries said. "When I unfolded it and read the first few lines, I couldn't believe what I was reading."

An Unlikely Informant

The letter was dated from 1962, written by a man named Albert Visser. It was addressed to Simon Wiesenthal, a famed Austrian Nazi hunter who had recently concluded the high-profile case of Adolf Eichmann, one of the main architects of the Holocaust. Within his letter, Visser detailed how his nine-year-old daughter, Mina, informed the Nazis as to the whereabouts of two Jewish children.

"It read like a guilty confession," deVries said. "This man was tormented by what his daughter had done, and how it lead to the deaths of five people. He was writing to beg for forgiveness, and hoping that Wiesenthal could help him track down any living relatives of the victims."

Stories of Dutch collaboration with the Nazis are not uncommon, but it was uncommon for a child to be an informant. Many stories involved profit as the motive, since the Nazis offered rewards for information about Jewish people in hiding. The heartbreak found within Visser's story makes it unique, deVries said.

"I really felt for the father," he said. "He was heartbroken that his daughter essentially destroyed the lives of so many people."

The information that Mina provided to the Nazis led to the discovery of her Jewish classmate, Lies Meijer, and Lies' six-year-old brother, Jakob, hiding in a crawlspace beneath a building in Rotterdam on Oct. 13, 1943. The building's owner, two Dutch helpers and Mina's school teacher were also arrested. Only one of the people arrested that day survived the end of the war.

Visser detailed how his daughter discovered her former classmate and the chain of events that lead to her taking the information to the Nazis, lamenting that if only Mina had told him first, he could have warned the people involved.

"You could see how he blamed himself," deVries said. "All through the letter, he talks about how he wished he knew about what his daughter saw, how he wished that she had confided in him, and that he was ashamed of himself as a parent, that his daughter could not understand the consequences of her informing."

The Prettiest Girl in Class

Lies Meijer was, by all accounts, a charming and precocious girl. She was born in Arnhem in 1934 and her family moved to Rotterdam in 1938, where her father, Viktor, oversaw operations for a small importer. Most of the goods coming through her father's warehouse were destined for Nazi Germany. The family stayed in the city despite the fact that many buildings and areas were destroyed by the Luftwaffe in 1940, though her father's business suffered greatly after the Nazi occupation of the Netherlands.

At school, Lies was an excellent student, earning high marks in nearly every subject, recalled one of her former classmates, Gert Jansen. Jansen, who recently turned 84 and still lives in Rotterdam, remembered the girl well.

"Lies was always the first one with the answer to a question," he said. "She was so friendly and smart as a whip."

Jansen said he had a crush on the girl, something his parents discouraged because she was Jewish.

"Not that I would have done anything about it," he recalled. "I was seven years old and incredibly shy, and she was the prettiest girl in the class."

The class also included Mina Visser, whose family was more wealthy than most, Jansen remembered.

"I always remember Mina having nice clothes," he said, admitting that he did not interact much with her. "It's not that she was overly mean or unapproachable, but the boys didn't mix much with the girls at that age."

Many of the Jewish children began to disappear from the class in 1941, he remembered, if only because his crush was no longer there.

As it turned out, Lies and her brother Jakob were sent away to hide with friends in late August 1941. Their parents were unable to escape and were sent to Westerbork, a transit camp in the Netherlands. Nazi records indicate that Viktor Meijer stayed in the camp for about six months starting in July 1942, before being transferred to Sobibor. He died there in 1944, unaware of the fate of his children. Lies' mother, Marie, was sent to Bergen-Belsen, where she died of typhus in late 1942, according to camp records.

Jansen admits he was too young to give much thought to the political climate of the time, and did not ask questions about what happened to Lies or any other missing Jewish children.

"I was too caught up in being a kid, I guess," he explained. "After the war, when I was a little older, I wondered whether some of them had survived. It was different then, there really wasn't any way to find out about them. You were just left to wonder."

Getting Answers

The tale penned by Albert Visser fascinated Luuk deVries, but he had no idea what to do with the letter. He eventually took it to Amsterdam, to a museum dedicated to the Netherlands' most famous Holocaust victim, Anne Frank. The museum helped deVries launch his own investigation into the story behind the letter.

"So many of the records were destroyed during the war," he said. "I would find bits here and there, but piecing together the whole story took a long time. I think I worked on it for the better part of two years."

He finally was able to match up German records from Westerbork with Lies, though her last name was spelled using the German variation of her name, "Meyer". From there, he was able to track down information on what happened to her, and eventually, the rest of her family.

"It helped complete the puzzle, so to speak, since Albert (Visser) wasn't aware of exactly what happened to Lies or her brother," deVries said. "He was told they had likely died, but he didn't know the details."

The letter was part of an effort Albert Visser was making to learn those details, though he ultimately did not mail the letter. He died in 1974 of lung cancer.

"I think, at the time, Simon Wiesenthal was the most famous person in the world associated with finding information about the Nazis," deVries said. "It makes sense that he'd want to write to him, hoping that he could find something out, get this information to the victim's families, and maybe try to set things right."

When Lies was discovered in the crawlspace with her brother, Jakob, the pair was initially taken to Westerbork for processing. From there, records indicated that Jakob was sent away the following week for Auschwitz. He apparently died during the trip, but deVries said the Nazi files do not mention how. Children arriving at Auschwitz in 1943 were typically executed upon their arrival, so it is at least unusual to deVries that the Germans would have recorded his death as "in transit".

Lies was ordered from Westerbork to Theiresenstadt, a camp located in the current Czech Republic, one week after her brother. She died of complications from hypothermia on Nov. 13, 1943, after the camp commandant ordered inmates to stand outside in freezing temperatures the day before. The camp was not known for having children, but deVries could not find any documentation explaining why she was included in that particular transport.

"Unfortunately, that's a part of the mystery that will remain a mystery to me," he said. "Children generally were not useful as labor, and were normally sent to Auschwitz. Why Lies Meijer was sent to a labor camp is anyone's guess."

The Price of Helping

Albert Visser also expressed remorse about the deaths of three Dutch people, accused of helping the Meijer children in various ways. The owner of the building where the children were hiding, Maarten der Sloot, knew about the children and occasionally supplied them food, though he was not their primary caretaker.

That task fell to his secretary, Mies Woltheis. The 23-year-old woman would often sneak into the building at night to bring the children food and teach them basic lessons in math and reading. The children were moved by sympathetic Dutch citizens several times during their time in hiding, ending up in the crawlspace under der Sloot's accounting office in March 1943. They would remain under the floor, usually sleeping, during the day. They would come up into the office through a secret door during the night, where Woltheis would feed them. The Dutch helpers had no previous connection to the Meijer's; the children had started in the care of family friends, but were moved after several close calls.

"The fact that these total strangers took it upon themselves to hide these children is amazing to me," deVries said. "The personal risk was grave, especially for children that you didn't know." Woltheis and der Sloot ultimately both died of typhus in Auschwitz, having been sent there for sheltering the Jewish children. Woltheis' boyfriend, Klaas Boere, would also bring food to the children. He survived the concentration camp and took over der Sloot's accounting business. Boere died in 1986.

Albert Visser had located Boere in 1956, and tried to find out what he could about the children's fate.

"He was torn, because on one hand he wanted to know, but he also didn't admit to the part his daughter played," deVries said. Boere, who was reluctant to discuss the subject with Visser, told him he believed the children had died in the hands of the Nazis.

Discovery

When Albert Visser arrived home from work about a week before Lies Meijer and her brother were discovered by authorities, the family cat bolted past him and out onto the street. His daughter Mina chased after it. A few blocks away, she cornered the cat near the accounting office of Maarten der Sloot, but the animal ducked beneath the building. Mina could not fit through the space to follow, but she peered inside. Lies and her brother were sleeping. Mina recognized her classmate because of the unmistakable birthmark on her arm.

"It's strange how life works," deVries said, recalling Albert's narrative of the events surrounding Lies Meijer's discovery. "If the cat doesn't get out, if Mina doesn't chase it, who knows, maybe Lies and her brother are never found and they survive."

The cat returned on its own later that evening, after Mina had gone home and confided what she saw in the crawlspace to her mother.

"They both decided to keep it a secret from him," deVries said, referring to Albert. Instead, her mother told her it is best not to interfere with the Germans, not to antagonize the Nazis by helping the Jews. Her father felt this made his daughter believe that turning in her classmate was the right thing to do.

The next day, Mina approached her teacher, Nels Biekhart, about what she saw, telling her about the hiding place and that she was certain Lies Meijer was under the building. Albert can only speculate as to Biekhert's reaction, because the teacher neither warned the children nor told authorities.

"She told Mina that she would take care of it," deVries said, however the teacher did nothing. But the girl grew impatient that she hadn't heard anything about the arrest of hidden Jewish children, and decided to approach the Germans herself. Albert admits being disappointed in his daughter's decision, and openly questioned her motivation.

"There's the underlying impression that Mina is jealous of Lies. Lies is pretty, Mina is more plain. Lies is smart, Mina is average," deVries said, describing Albert's letter. "He expressly says that his daughter was lured by the promise of money and rewards for the information, but he dismisses those things as an excuse to cover her underlying motivation."

The Germans watched the building for a few days, watching who came and went before making their arrests. The Vissers also fell under suspicion, as the Nazis were not convinced the Jews were found in pursuit of a lost cat. While this was the first time that Albert had heard about Lies, her mother pretended that she was also surprised to learn the information. Only later did Albert learn that Mina had told her nearly a week earlier. The authorities finally relented with their suspicion of the family when Mina offered that she told her teacher about Lies, and that the teacher did not pass along the information.

An Unlikely Victim

"One of the saddest parts of the story has to be what happened to Nels Biekhert," deVries said, referring to Mina Visser's teacher. "She was jailed for knowing about the hiding place and not reporting it immediately to the authorities. The Germans made an example of her."

Biekhert was taken to the Gestapo office in Rotterdam, under the auspices of finding out whether she was withholding other information. It was the last time anyone would see her alive, other than her German interrogators.

The circumstances surrounding Biekhert's death are more clouded than the others, she died in Gestapo custody during questioning. The investigation by deVries uncovered a shocking detail.

"There are stories that some of the Gestapo agents in this office would trump up reasons to bring pretty Dutch women in for 'questioning'," he said. "I don't think I have to say what that implies. It's pretty clear something went wrong that night, and Nels Biekhert didn't survive."

While her death was not officially reported by the Germans, Albert later heard about her death through gossip around town, according to deVries. Records from the office were destroyed ahead the Allied liberation of the city in May 1945.

"There were many instances of brutal behavior by the Gestapo in respect to the Dutch, but it was unusual for someone to die during questioning," he said. "Even the Gestapo were held accountable to some degree, and this would have required some kind of explanation."

Another Life Claimed

When the promised reward arrived, Albert is horrified that both his wife and daughter readily accepted the money.

"The whole sequence of events had stunned him," deVries said. "Then his own family almost revels in the rewards. It's too much for him to take."

Near the end of the letter, Albert expressed regret that he told both his wife and daughter in no uncertain terms that he believed the Nazis were at least taking the Jews to use as forced labor in the war effort, maybe worse. Things got worse when the family found out that Biekhert was dead.

"His daughter basically became withdrawn and sullen," deVries said. While Mina regretted what she had done, Albert said she was consumed with guilt. Mina took her own life in 1958. The event caused the Vissers to separate and eventually divorce. Mina's mother died in 1981.

"This all started with Shangri-La," he said, referencing the mythical city in Hilton's Lost Horizon. "It ended with a story far more remarkable and sad than that one."