Years ago, I ran FASA's Star Trek: The Roleplaying Game for my group. We had a nice, solid, thriving campaign set on a Constitution class vessel, the USS Valiant (NCC1718), set around the time of Star Trek II:Wrath of Khan. During one mission, the crew encountered a threat of some sort, and one of the indications that something wasn't right was the fact that the planet's moon was recently shattered by some tremendous (if unknown) force. However, the moon wasn't central to the plot. It was simply collateral damage. However, the Chief Navigator was convinced that the moon's destruction was important. He didn't let it go. He kept harping on it, researching it, whatever.
So anyway, the players immerse themselves in the storyline and tackle the challenges. The adventure progresses nicely. One of the characters, who was actually the ship's Captain, finally figured out what was going on, what was behind it, and how to stop it. He called a meeting in the briefing room, and, like Sherlock Holmes explaining the mystery's solution at the end of one of his tales, gave this brilliant presentation where he pretty much nailed it.
The room went quiet. Everyone was absolutely floored by the Captain's presentation. They now had the means to beat the adventure. Suddenly, the Chief Navigator pipes up "Well, that's all well and good, but you still haven't explained how the moon got destroyed." The rest of the room erupted in good-natured exasperated laughter.
From that point on, whenever a character came up with the solution to a problem/trap/challenge/entire storyline, someone would inevitably pipe up with "Well, that's all well and good, but you still haven't explained how the moon got destroyed."
