Cass smiled at James' comment, though he really wasn't going to take the woman's word for it so readily. Yes, his gut told him she wasn't lying, but everything he knew about magic told him that it was impossible. It made no sense what so ever.
He reached out, handing the glass container to the woman. "You should know how it works," he said. "We'll give it a moment to work, I'll ask you some random questions and I want you to try to lie to at least one, then we keep going with the real questions."
He paused, looking at James. Had he been so ready to trust his gut even when things were impossible at that age? He pushed the thought away and looked back at Tonks. "If you answer the same as now when you're on the potion, we'll contact Ted."