Yeah, that's "Leela's Homeworld" (prod.-code 4acv02).
On the airing season I've to correct nosebleed (
), it was also airing-season 4 (AniVCD-code S04E05), same as the episodes "Lova and Rocket" (4acv02 / S04E04) and "Where no fan has gone before" (4acv11 / S04E12).
The rest of production-season 4 (4acvXX) was aired as a 5th season (S05Exx) together with the episode "The Route of all evil" (3acv12 / S05E03) from production-season 3.
Enough with the nitpick
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