Jeremy Slater Creator Steve Blackman Creator, Executive Producer Gabriel Bá Creator Elliot Page Vanya Hargreeves, Viktor Hargreeves Actor Tom Hopper Luther Hargreeves Actor David Castañeda Diego Hargreeves Actor Emmy Raver-Lampman Allison Hargreeves Actor Robert Sheehan Klaus Hargreeves Actor Aidan Gallagher Five Actor Justin H. Min Ben Hargreeves Actor Ritu Arya Lila Pitts Actor Colm Feore Sir Reginald Hargreeves Actor Nick Offerman Dr. Gene Thibedeau Actor Megan Mullally Dr. Jean Thibedeau Actor David Cross Sy Grossman Actor Javon "Wanna" Walton Stan Actor Justin Cornwell Marcus Actor Britne Oldford Fei Actor Jake Epstein Alphonso Actor Genesis Rodriguez Sloane Actor Cazzie David Jayme Actor Adam Godley Pogo Voice Cameron Britton Hazel Actor Kate Walsh The Handler Actor Yusuf Gatewood Raymond Chestnut Actor Marin Ireland Sissy Actor John Magaro Leonard Peabody Actor Ashley Madekwe Detective Patch Actor Mary J. Blige Cha-Cha Actor Mike Richardson Executive Producer Keith Goldberg Executive Producer Beau Bauman Executive Producer Jesse McKeown Executive Producer Scott Stuber Executive Producer