Realizing the treaty ports in Japan were scheduled to open on July 1, 1859, Heco left his ship and went to Hong Kong. Here he joined Townsend Harris, returning to Japan on the U.S.S. "Mississippi". In Shanghai, Heco also met E.M. Door, scheduled to be the American Consul at Kanagawa. Heco accepted Door's offer of a job as his interpreter. Heco left Shanghai on June 15, 1859, and arrived at Nagasaki. Heco had been asked to stay in the background, but following an incident between an American sailor and a Japanese, he intervened when the Japanese interpreter did not know enough English to handle the situation. The Japanese interpreter was dumbfounded and questioned Heco closely. The "Mississippi" left Nagasaki on June 22 – without Heco ever setting foot on land.