James May: Oh Cook! (2020)

S5E16 Invaders from Outer Space: The Coming of Siren

Usagi and Lina stumble upon a seemingly lost little girl during their day out. After a fun-filled adventure, they head back home, only to be taken aback when they discover that the same girl has moved in as Usagi's new younger sister. The sudden change leaves them both puzzled and curious about the mysterious girl’s origins.