“Not to be Ms. Basil Exposition or anything,” Zoe interjected, “but can you explain to me why having all these extra time travellers is so bad?”

“Letrodacta’s sociopathology has turned into psychopathology over the many centuries and millenia she has been alive,” said Al. “Her longevity has driven her insane.”
He turned to me.
“It was your belief that she no longer wanted to live, but that she also didn’t want to take the chance that she could come back to life and live for millenia over and over again for all eternity. You theorised that she wanted to destroy the universe, in order to destroy herself. It was not an unreasonable hypothesis.”

“You haven’t answered my question, Al,” Zoe said irritably.

“Having a few time travellers in one universe is bad enough,” he said. “Having a few hundred, on the other hand, is much worse. With all the overlapping timelines, accidental paradoxes and everything else, the universe would eventually implode.”

Officially, Al now had a bombshell hat-trick.