"Timetagger" balances high-concept sci-fi with grounded character work:
Seeing their adult silhouettes provides a "north star" for their development. It reassures the audience (and the characters) that they eventually succeed, even if the road is difficult. [S3E18] Timetagger
"Timetagger" is more than just an action episode; it is a structural pillar for the Miraculous mythos. It provides the audience with "spoilers" that don't actually ruin the surprise, but rather deepen the intrigue. It proves that while Ladybug and Cat Noir are currently teenagers finding their way, they are destined to become legends. they are destined to become legends.