* BigLippedAlligatorMoment: The time tunnels, AfterlifeExpress, and that planet with the memory-stealing spirit are all ''radically'' at odds with the tone of the rest of the series, and none of them are ever mentioned again.
* TearJerker: Every episode to some extent has one, especially when minor characters die.
** [[spoiler: Bruce's death]] if you want to go that far.