On the outbreak of hostilities with Japan in December 1941, the Rycrofts initially agreed to help with the war effort by housing 3,000 soldiers in the factory drying sheds and sending some of the workforce to help prepare an airfield away. However, by January 1942 Charles and Muriel had left the Harcroft Estate, fleeing to Singapore via Kuala Lumpar. Muriel was allowed passage on the last ship out of Singapore in February 1942, which took her to Colombo and then Bombay (now Mumbai). After a short period, she travelled onward to Cape Town, South Africa. She rented an unfurnished self-catering room at the Belmond Mount Nelson Hotel for the rest of the war. Charles had to remain behind and volunteered to help in the auxiliary fire brigade. The Japanese had not expected that they would capture Singapore and were therefore unprepared to run the city, meaning Charles was able to remain in the fire brigade for some months. Eventually, though, he was transferred to the Changi internment camp for civilians (next to the infamous Changi POW camp), where he remained until August 1945. Civilians were allowed one trunk of personal possessions, and Charles packed his trunk full of tinned and dried food, rather than the photos and personal items that most other inmates took. He also followed the advice of the camp doctor to eat the maggots in the food as an extra source of vital protein, rather than pick them out as others did. Due to these factors and good luck he was one of the relatively few who survived to the end of the war. There is a portrait of him by the Russian artist Vladimir Tretchikoff and fellow camp inmate showing his bearded and rather skeletal appearance at the end of the war.