"You did say that," he agrees, all pleasant demeanour and professional bearing. He remembers the details from the report - his copy's marked up with notes and question marks. "But you must have had a theory, right? Even if you couldn't make it the official story, you had an idea of what did that."

As buttoned-up and professional as she is, Mulder doesn't want to push too hard - not yet. But there's something about prim Ms. Scully that makes him suspect that friendly curiosity might not convince her to spill the details without more prompting.

Only one way to find out.