At Oxford, Keaton met and later married his wife, who was a mathematics student at Somerville College. The couple years later divorced, with Keaton leaving his five-year-old daughter Yuriko in her mother's care. After leaving Oxford, Keaton joined the British Army and became a member of the SAS, holding the post of survival instructor and seeing combat in the Falklands War and as one of the team members that responded to the Iranian Embassy siege. His combat training serves him in good stead as an insurance investigator for the prestigious Lloyd's of London where he is known for his abilities and his unorthodox methods of investigation.