Kogoro is hired as a bodyguard for a woman who has been receiving death threats. The letter warns she will be killed at 6:00PM at her birthday party.

Kogoro and horse bettors Susumu Nakamura, Chihiro Ougi, Masao Shinohara gather in Satsuki Mishima's bar, one with no leg room and with a crack in the rusty wall. Everyone then leaves the bar around the same time to attend to personal matters. Kogoro takes a smoking break, Nakamura goes to buy cigarettes, Ougi to the public restroom, Shinohara to the ATM. When they regroup, they find Satsuki slouching over the counter on a swivel chair. Shinohara tries to wake her up, only to find a knife in her chest. Kogoro assumes that during the break, someone had a fight with Satsuki who was behind the counter, and stabbed her in the front. The evidence left on the scene does not support it.