The First Doctor is taken from any of the following moments: the escape to the TARDIS in ‘An Unearthly Child’; his confrontation with Ian and Barbara in ‘The Edge of Destruction’; or his attempt at escape on Kembel as the Time Destructor activates at the end of ‘The Daleks’ Master Plan’.
The Second Doctor being taken away during the final fight in ‘The Enemy of the World’ would be horrible for Jamie and Victoria. Salamander would win! Alternatively, plucking the Doctor out from the Land of Fiction would be just as dire for his companions…
The Third Doctor coming fresh from ‘The Green Death’ would be interesting, if only to see how different he is with Jo’s departure so fresh to him.
The Fourth Doctor during Season 16 would be fascinating. Would he be worried that the Black Guardian might follow? Could the Black Guardian follow? If not, take him during the E-Space trilogy so Romana or Adric end up stranded for a little while, meanwhile we end up with a more dour Doctor from Season 18, haha
The Fifth Doctor… It’s tempting to say either immediately after ‘Earthshock’/just before ‘Time Flight’, or even during his journey back to Peri in ‘The Caves of Androzani’, but I think it would be funnier if it was after ‘The Five Doctors’—he’s just dealt with his past, and now he’s got to (potentially) deal with his future!
The Sixth Doctor during ‘The Twin Dilemma’ feels like the only right call. But, if post-regeneration stories are off limits, then I’ll choose the aftermath of ‘Mindwarp’ with that grief still fresh.
The Seventh Doctor would depend on if expanded material counted. I imagine it’d be a toss of the coin if he showed up from the Timewyrm arc, what with how not-all-there he was. I’ll settle for ‘Remembrance of the Daleks’, however, hopefully with the inclusion of some contemplations from the Doctor about the consequences of his actions…
The Eighth Doctor would need expanded material to count, but there’s far too much for me to choose from. I’ll choose ‘Terror Firma’; have the Doctor terrified that he’s abandoned Charley and C’rizz just like he did Samson and Gemma…
The War Doctor goes without saying. I feel like any day would be the worst for him, and we’ve already seen him on the Last Day…
The Ninth Doctor right after his argument with Rose in ‘Father’s Day’. I feel like he’d be a uniquely prickly type in that context.
The Tenth Doctor during his Time Lord Victorious moment in ‘The Waters of Mars’. I imagine he’d try everything he could to escape and get back to Bowie Base One. But, if he didn’t, I’m sure he’d be terrible company for the other Doctors…
The Eleventh Doctor just before going into self-imposed exile after losing Amy and Rory. Again, the grief—I feel like there’s a pattern here…
The Twelfth Doctor during ‘Hell Bent’. I don’t think that warrants explanation.
The Thirteenth Doctor is one I still can’t comment on, but I’m going to hazard a guess and say that she might not be ideal to be around if she’s taken from the moment she learns about the Timeless Child…
The Fugitive Doctor is a tricky one. Let’s just say at any point; I feel like most other incarnations would have a very difficult time with her, not that she’d care, haha
The Fourteenth Doctor between ‘Wild Blue Yonder’ and ‘The Giggle’, ideally before the TARDIS lands and he sees Wilf.
The Fifteenth Doctor during ‘The Interstellar Song Contest’. That wouldn’t be pretty…