Ben Diskin

Nigel "Numbuh One" Uno / Hoagie Pennywhistle "Numbuh Two" Gilligan Jr. / D.C.F.D.T.L. (Voice)

Lauren Tom

Kuki "Numbuh Three" Sanban (Voice)

Dee Bradley Baker

Wallaby "Numbuh Four" Beatles / D.C.F.D.T.L. / Chip / Toiletnator / Mr. Fibb (Voice)

Cree Summer

Abigail "Numbuh Five" Lincoln / D.C.F.D.T.L. (Voice)

Maurice LaMarche

Father (Voice)

Ric Stoneback

Adult Hoagie

Sonnie Brown

Adult Kuki

Jeff Bennett

Mr. Boss (Voice)

Jennifer Hale

Computer / Mrs. Uno / Numbuh 86 / Numbuh 363 (Voice)

Mark Hamill

Stickybeard (Voice)

Janice Kawaye

Sonia / Lee (Voice)

Tom Kenny

Mr. Dink / Knightbrace (Voice)

Rachael MacFarlane

Numbuh 362 (Voice)

Frank Welker

Mr. Uno (uncredited) (Voice)

Candi Milo

Lydia Gilligan (Voice)

James Arnold Taylor

Nick (Voice)

Daran Norris

Count Spankulot (Voice)

Rob Paulsen

Robin Food (Voice)

Fred Tatasciore

Cheese Shogun Roquefort (Voice)

Dave Wittenberg

Numbuh 74.239 (Voice)

Curt Hostetter

Adult Numbuh 4

Fran Jaye

Adult Numbuh 5

Codename: Kids Next Door: Operation Z.E.R.O.

The Grim Adventures of the Kids Next Door

Codename: Kids Next Door: Operation I.N.T.E.R.V.I.E.W.S.