"Space Babies," the first episode of the new "Doctor Who" season, introduces the Fifteenth Doctor (Ncuti Gatwa) and his new companion Ruby Sunday (Millie Gibson) to a spaceship full of talking infants — and a slobbering monster with some very icky origins.
But, in an episode packed with exposition about the Doctor's two hearts and his space-and-time-traveling TARDIS phone box — not to mention a few teases about Ruby's mysterious backstory — it's perhaps the Time Lord's references to being "the last of the Time Lords" that carry the most emotional resonance. Here we explain why the Doctor is alone in the universe. And if you're wondering how to watch Doctor Who, check out our Doctor Who streaming guide for how to tune in from anywhere.
