Cadence Birdwhistle was a forensic accountant for MI6 who was undercover at the Turkish Consulate in Los Angeles. While working there she discovered some illegal transactions but in doing so broke her cover, so Agent 007 was sent to extract her before the Turkish government could harm her. As they drove to the airport they were attacked by MIT operatives from the Turkish government, but Bond managed to escape them. Unfortunately, the Los Angeles International Airport had been temporarily closed due to a bomb threat.
She and Bond stayed at an MI6 safehouse, but were attacked by two CIA agents at the airport the next day. Then, while pulling out of the Heathrow airport, they were attacked again by two gunmen, but were unharmed due to their heavily armored car. They got back to the MI6 headquarters at Vauxhall Cross, where she, with the help of an I-Branch specialist, traced the money back through MI5 with shell companies called "Eidolon". She, M, Miss Moneypenny, and MI5 agent Eve Sharma then presented their findings to the Commissioner of Defense, who was killed by MI5's head Sir Stephen Mackmain of MI5, and so Sharma and 007 gave chase to the other assassin, Beckett Hawkwood of the Eidolon cell within MI5, but he escaped.
While walking through London to bring some additional research to the government, Birdwhistle discovered Hawkwood in town. She called Bond, who had been tailing her with two other operatives, who were quickly defeated, but 007 was able to corner him and defeat him.
- Birdwhistle's peculiar name is descended from the German surname "Birtwhistle".