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Tear Jerker: Dinosaurs
The ending of "Nuts to War (Part 2)" (where Earl tries to snap Robbie out of being a bloodthirsty warlord) is both this and a Heartwarming Moment.
The final episode, especially the last five minutes. A new ice age is forming, the dinosaurs are doomed, and everyonenote except maybe the cavepeople from the series is going to die. But what really drives it home is when Baby asks what's going to happen to them. Earl and Fran don't say anything, but from the way they look at each other, it's clear that they know they're not going to make it.
The final words of the series.
Howard Handupme: And taking a look at the long range forecast: continued snow, darkness, and extreme cold. This is Howard Handupme. Goodnight... goodbye.