A Dispute Over a Platinum Ticket

While Ran, Sonoko and Conan go to a coffee shop after getting a popular concert ticket, another customer arrives with her friend and loses her ticket there. The next day, she comes back showing the same ticket auctioned off on the internet. While the three along with the manager, another employee and the customer go to the home of another employee who hadn't arrived to work, they find her dead. The house appears to have been robbed.