Oh, I get it! Okay, okay, with that, then, here's Misa-Misa's theory. So the killer pushed Tarrlok down the stairs. Then Lynne, on the first floor, found the body and started to investigate. And the killer's hiding upstairs! So Lynne sees the killer in the middle of her investigation, and there's a chase all the way up to the dojo! And that's where stuff happened! Does that seem believable?