Episode 400: Ran's Suspicions
Scenario: Ran suspected that Conan and Shinichi are the same person. She took Conan's phone secretly and tries to find out if the message sent to Shinichi will recieved by Conan's phone. Somehow, she's having trouble to unlock the PIN number the whole night. Ran turns on Conan's cellphone only to find out there is a four digit lock. She reminisces about the time Shinichi was forming words through the Hiragana and numbers found on the license plates. Shinichi witnesses a car with an illegal license plate as cars are not allowed to use the Hiragana "shi" or "he" and reports this to the police.
The police capture the criminals before they robbed a bank. Back in the present time, Ran uses the word Sherlock which are the numbers 4869 and unlocks Conan's phone. Ran suspects Conan deleted her messages and resents the mail only to receive a phone call from an irritated Shinichi. Conan appears and asks for his phone and returns to his room where it is revealed that he used a prerecorded message to call Ran in the event of her getting close to finding his secret. Conan then gives Ran his phone number and accepts the dangers that would come by doing so.