Volcano!

Stanley and Ted stood atop a massive volcano. Having spent the better part of an afternoon climbing, there they were, staring into a fiery pit.

"I say Stanley," said Ted, "are you quite sure this volcano is safe?"

"Not at all," replied Stanley.

"I see," said Ted. "But we're quite sure this volcano isn't scheduled to erupt?"

"Oh no," replied Stanley.

"Well, that's a relief," said Ted.

"Oh, no," replied Stanley. "I meant, 'Oh no' in the sense that I'm not sure."

"I see," said Ted. "I would assume the chances of eruption are quite small."

"I should think so," replied Stanley. "This particular volcano erupts but once a week."

"Stanley," said Ted, "you know it irritates me a great deal that you didn't investigate this more thoroughly. In fact, I'd say I'm downright enraged."

And then, as if to signify Ted's rage metaphorically, the volcano erupted.