Russell T Davies having the Doctor regenerate into Billie Piper hoping this would resurrect interest in the show, only for the twist to be mocked to hell and back by everyone & make both fans and the general public turn on it even harder
Well you see, Jodie Whittaker regenerated into a new Doctor who happened to look like David Tennant who then split by mitosis into himself and Ncuti Gatwa. Gatwa then left the show and the original plan was to leave his regeneration open ended but instead they rewrote it last minute, reshooting half the finale in order to facilitate his regeneration into Billie Piper, who was intended to be another temp Doctor for a special or two, which RTD committed to despite the likelihood another writer would have to reckon with that. To do this they not only cut out the original story arc, but scenes featuring Carole Ann Ford as Susan, which given she is 85 & the show is now on hiatus means her reappearance will likely go unresolved forever. This masterful RTD gambit secured Doctor Who a long term hiatus and his termination











