TheCodeBreakers
If Rochefort's
unit could solve these, Mayfield figured, he might know better which
Japanese to shadow and what information they sought.
His intuitions were sound. On March 27, 1941, not two weeks after
Mayfield himself took up his duties, a young ensign of the Imperial
Japanese Navy, 25-year-old Takeo Yoshikawa, who had steeped himself
in information about the American Navy, arrived in Honolulu to serve as
Japan's only military espionage agent covering Pearl Harbor. Under the
cover-name "Tadasi Morimura," he was assigned to the consulate as a
secretary. He promptly made himself obnoxious—and drew suspicion
upon himself within the consulate staff—by coming to work late or not at
all, getting drunk frequently, having women in his quarters overnight,
and even insulting the consul himself on occasion. But he managed to
tour the islands, and within a month was sending such messages as:
"Warships observed at anchor on the llth [of May, 1941] in Pearl Harbor
annaabi.ee 
