Kogoro and Conan are hired by a barmaid to find her missing pet "Armadillo-kun." The driver of the taxi they hire during their search turns out to be a huge fan of Kogoro and begins telling them about the suspicious brothers who rode in his taxi earlier...

Conan, Haibara, and the Detective Boys are watching birds, but Conan proposes another game to them called "human watching". While teaching the Detective Boys how the game works, trying to determine people's jobs and occupations by watching them, they stumble upon detectives Takagi and Chiba apparently on a stakeout.