Detective Conan episode 878
It aired on Saturday, 28 October 2017.
The Blind Spot in the Dressing Room (Part 1)
As Ran, Sonoko, and Sera try on swim suits, Conan wonders through the department store and overhears a lady accosting the other people near her dressing room. After Conan leaves, he later hears a scream from that area. The rude woman turned up dead.