He devoted himself to reviving the hand-weaving of silk, which had been lost as a cottage industry in Thailand. He is also well known for the construction of a traditional complex of six Thai houses in the middle of Bangkok. Most of the parts of his teak houses were disassembled from places around Thailand. They are now a museum and are a popular tourist attraction.
Thompson disappeared after going on a walk in the Cameron Highlands in Pahang, Malaysia, on March 27, 1967. He was never found, and there are many theories for his disappearance, many of them pointing to his former days with the OSS.