Doctor Who attracts so much media attention that it's difficult to go into each new series knowing absolutely nothing.
If you're a part of any Doctor Who online community - even casually - you've probably already seen those leaked set photos from Series 13, which revealed things that would've been nice to see for the first time on the small screen. Or even in a trailer!
But still, this is a show that does pack plenty of surprises. Away from reveals that were either obvious (the Doctor is the Timeless Child - duh) or spoiled by the BBC itself (Series 10's John Simm Master reveal - sigh), there are many moments in Doctor Who history that likely had your jaw magnetised to the floor.
So many, in fact, that we've already done a list on this very subject. Twists galore!
Here though, let's run down ten new moments - moments that, whether they had you laughing, crying, or scratching your head, undoubtedly caught you off guard. Doctor Who is anything but predictable - and the last 50-odd years has been quite the WTF ride.
10. The Regenerating Child
Series 6's Day Of The Moon ended like most other episodes of Doctor Who: the main gang (in this case, Amy, Rory, and Eleven) is back in the TARDIS, bantering around, reflecting on the adventure they've just returned from.
But wait, what's this? There's an extra, MCU-style tag at the very end? The story suddenly skips ahead six months to a dank New York back-alley, which is a very jarring turn at first - that is, until the mysterious young girl we'd been tracking throughout the last two episodes emerges from behind a bin.
Things get very weird, very fast when she casually tells a nearby homeless man "I'm dying - but I can fix that". And then - in a truly what the hell moment - her hands start to glow with that iconic golden energy, and she bursts into a full-on regeneration.
We first met this girl in the previous week's episode, so there were already a lot of theories about her possible identity. But wherever you stood on the matter, nobody expected her to regenerate here. That look of shock and confusion on the homeless man's face was pretty much reflective of the viewing audience at home.