On 16 November 1942, Fritz Pfeffer went into hiding in the Secret Annex. He was the dentist of Miep Gies and an acquaintance of Otto and Edith Frank. His fiancé Charlotte Kaletta had been a guest at the wedding of Miep and Jan Gies the previous year.
Pfeffer had told his landlord that he would be hospitalised. He was surprised to see the Frank family again. He had heard that they had fled to Switzerland. Fritz was to share Anne’s room with her. Before his arrival, Margot had slept there; from then on, she slept in her parents’ room.
Charlotte was left behind. She was not Jewish and not in danger of being arrested by the Nazis. He did not tell her where he went, so she could not accidentally betray him. He missed her very much, but they stayed in touch. They wrote letters to each other, and Miep Gies acted as their messenger.