The most difficult keys to "wax" are the two keys at the train station. Pierce plans to copy them at night, but the presence of "crushers" (policemen) and "jacks" (security guards) forces him to recruit "Clean Willy" Williams, a "snakesman" or burglar able to slip inside buildings through small and cramped openings, who is currently incarcerated in the high-security and supposedly escape-proof Newgate Prison. Pierce sends a message through Willy's former mistress and assists Willy in escaping from Newgate while the public is distracted by a public execution outside the prison. After nursing Willy back to health from injuries received during the escape, the criminals succeed in making wax copies of the two keys at the railway station, completing the job with only seconds to spare before detection.