Peter Capaldi
The Doctor
Alex Kingston
River Song
Greg Davies
King Hydroflax
Matt Lucas
Nardole
Phillip Rhys
Ramone
Rowan Polonski
Flemming
Robert Curtis
Scratch
Anthony Cozens
Concierge
Chris Lew Kum Hoi
Alphonse
Nicolle Smartt
Receptionist
Liam Cook
King Hydroflax's Body
Nonso Anozie
Voice of Hydroflax (voice)
Clem So
Starline Galactic Villain (uncredited)