This episode starts revealing the story behind Ishigami village and the 6 people that avoided the phenomenon that turned everyone on Earth to stone, as they were in space as it happened. They all try to figure out what to do as the only people alive who weren't stone, and honestly it's pretty heartbreaking. This and the next episodes made me very sad as their story is told. Not quite enough to make me cry, but you may need tissues for these episodes as there are some very heartfelt and sad moments. But that always makes it better for me (I Like to have my heartstrings pulled occasionally!)
Whoever said this felt like a filler episode obviously missed the point entirely. Backstory of the main characters is one of the most crucial parts of the story, and how anyone can consider it "filler" is beyond me. These characters are very important and you will surely like them!