10 Longest Pay-Offs In Doctor Who History
4. River Song At The Singing Towers
When the Doctor first meets River in the library in 2008's Silence in the Library, she sacrifices herself to save the day. River is heartbroken that this Doctor doesn't know her and promises that she knows him VERY well, even hinting that they are married.
In her dying moments, she name drops certain adventures and talks about their last meeting when the Doctor turned up with a haircut, a new suit and took her away for a romantic get away at the Singing Towers of Darillium.
River returned multiple times over the next few years, appearing in the adventures that she had mentioned in her final moments, like the crash of the Byzantium. Her time with Eleven saw their relationship blossom through their adventures and lead up to their marriage.
After the Eleventh Doctor regenerated, the Twelfth Doctor wasn't lucky enough to meet River until after Clara's death. It was 2015's Christmas episode, The Husbands of River Song that took us to Darillium.
The episode's closing scene shocked viewers by appearing from nowhere and showing the heartbreaking scene which had been mentioned almost eight years ago. Needless to say, the emotional scenes in this unexpected pay off ruined everyone's Christmas