Kogoro, Ran, and Conan find a cat belonging to a rich British woman who offers to pay their expenses on a trip to London so Kogoro may share his detective stories with her friends. To get past airport security, Haibara offers Conan two antidotes to the APTX 4869 for the trip and back. At the Holmes museum, Ran calls Shinichi asking him if he wants a souvenir from London. His weak reaction causes Ran to angrily hang up. Outside the museum, a kid named Apollo Glass asks to see Sherlock Holmes to solve a code that will prevent a person from being murdered. Conan offers to solve the riddle by posing as Holme's apprentice. Apollo reveals a strange man gave him a note containing seven coded riddles, declaring someone in London will die if it is left unsolved. They learn from the police that many children received the same code which Conan speculates to mean a large number of people will die. Conan and Agasa separate from the group as they attempt to decode the riddles.