The Perfect Insider - Season 1 Episode 6 Crimson Resolve

Saikawa and Nishinosono return to the campground the next morning and tell the group about the murders. In the evening, they return to the lab. Nishinosono notices upon reviewing the surveillance video again that, when the cart emerged from Magata's suite, the elevator went from the basement to the roof. In a continuation of the dinner flashback, Magata uses the knife to kill her mother, and Shindō and Magata kill Magata's father as Yumiko arrives.