The Delightful Children From Down The Lane are villains from Codename: Kids Next Door.
The DCFDTL are "perfectly behaved" children bent of the destruction of the Kids Next Door Organization and the supremecy of adult over children. The DCFDTL are, for all intents and purposes, one single being, speaking in perfect sync, although they are capable of splitting as Lenny has been shown to do so. They don't usually fight physically, instead relying on their various minions to do so.
The DCFDTL's names are as follows: Bruce (short blond boy), David (tall brunette boy), Ashley (tall blonde girl), Lenny (helmet boy), and Ogie (brunette chubby girl).
The DCFDTL were once members of the KND themselves, but were kidnapped by Father and Delightfulized. The Delightfulization Chamber they were exposed to blown a fuse, resulting in the development of their "Hive Mind".