T-Rex: Alex Trebek announces his retirement from Jeopardy. 3 weeks later, the final episode airs. Of COURSE the show ends with Trebek.
T-Rex: It was always to end with Trebek.

T-Rex: The final contestants are Ken Jennings, IBM's NLP computer, and some dude!

T-Rex: The first round is all behind-the-scenes questions on Jeopardy's production: stuff only Trebek would know. Nobody gets a single correct answer. The Double Jeopardy round is even worse, as the first letter from each category spells out "TREBEK".
Dromiceiomimus: But if nobody has a positive score, then nobody can play Final Jeopardy!
T-Rex: ...NOT QUITE. Alex removes the facade from his podium.

T-Rex: Behind it is a standard Jeopardy lectern. He's been a secret contestant, all these years.
Utahraptor: His score's in the millions!

T-Rex: The final question is "Alex Trebek's favourite thing to do is this." Trebek writes down his answer and stares out across the audience as the music plays, almost drowned out by non-stop applause. 30 seconds later, the song ends, and in the perfect silence that follows, he reads what he wrote to the studio audience.

T-Rex: "What is -" he begins. His voice breaks. He collects himself and starts again. "What WAS... Jeopardy?"
T-Rex: His score doubles into the billions, the crowd loses their minds, and we cut to our last commercial.