Shinichi helps the police to solve the murder case. As an apology for what happens, he promises Ran that he will take her to the the new amusement park, Tropical Land, if she wins the next karate tournament.

Kogoro infiltrates a gang to help the police to catch them. However, the leader discovers him and threatens to kill Ran if he doesn't find which of his gang members killed his son during a robbery one year ago.