Operation Start is the 102nd episode of the Katekyo Hitman Reborn! anime.
Hibari starts knocking the Millefiore members unconscious one by one. The place he lured them to is revealed to be meant for attacks like this. The Vongola find out that one of the shopping malls' ducts lead to the Millefiore base. They enter the ducts, only to trigger a trap where lasers prepare to fire on them.