Catalyst (The Heroes Day - Part 1)

It is the 'Heroes Day' in Paris, where everyone is supposed to do a good deed. Distracted from her duties as Ladybug, Marinette has completely forgotten to plan her good deed for this day. In order not to disappoint her friends, she lies to them and everything becomes more and more complicated. But the nightmare just begins when Hawk Moth akumatized his assistant Nathalie to Catalyst, a super villain, to help him with his long-planned revenge on Ladybug and Cat Noir.