Also, the Doctor makes Zygons be bygones. Yeah, I know, it's not that funny, but that's how TV Guide described it in 1979, so every American who was a kid at the time is legally obligated to quote it every time this story is mentioned. The Zygons would later go on to star in porn for BBV. "Nessie in the Thames" is also the only example Moffat could think of from Classic Who of an alien invasion that couldn't have been covered up and therefore must have been erased by Amy's crack.