HOLY CRAP! So I'm watching futurama, and I just noticed that in the 1999 season 2 episode 1 show "I second that emotion" (Leela, fry, and bender travel down into the sewer to find nibbler which bender flushes down the toliet), Leela's parents appear!
Now, this is especially interesting because Leela doesn't begin looking for her parents (and eventually discovers them) until Season 4 Episode 2 "Leela's Homeworld", which doesn't air until 3 years later in 2002.
My mind has been blown!
Another note, They not only are the only people to walk onto the scene, but they are on there for about 3-10 seconds.
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