What-if...?

General: What if the (ordinal number) Doctor had been played by someone else?
General: What if (non-Doctor character name) had been played by someone else?
General: What if none of the episodes were lost?
What if Sydney Newman had stuck to the "no bug-eyed monsters" rule and not allowed the first Dalek story?
What if Terry Nation had gotten a Dalek TV series made in the USA?
What if William Hartnell had been written out in "The Celestial Toymaker"?
What if William Hartnell had not had arteriosclerosis?
What if they'd gone with a William Hartnell "clone" for the second actor to play the Doctor?
What if the program had been cancelled when William Hartnell left?
What if they'd made a third Peter Cushing "Doctor Who" movie?
What if Patrick Troughton had been killed when the Gravitron fell over during filming of "The Moonbase"?
What if Wendy Padbury had opted to stay with the program when Patrick Troughton and Fraser Hines left?
What if the program had been cancelled when Patrick Troughton left the series?
What if Roger Delgado had lived to do the "finale" that Barry Letts had planned for the character of the Master?
What if William Hartnell had been healthy enough to make a full appearance in "The Three Doctors"?
What if Elisabeth Sladen had drowned while filming "Revenge of the Cybermen"?
What if Elisabeth Sladen had returned to the series in 1980?
What if Tom Baker's relationship with Lalla Ward had been more harmonious?
What if K-9 and Company had led to a series?
What if Tom Baker had agreed to appear in "The Five Doctors"?
What if Tom Baker had gotten Doctor Who Meets Scratchman made as a theatrical release?
What if "Shada" hadn't been cancelled by strike action?
What if Louise Jameson had returned for the transition from Tom Baker to Peter Davison?
What if "The Two Doctors" had been filmed in New Orleans as JNT wanted?
What if Laurence Olivier had agreed to appear in "Revelation of the Daleks"?
What if the series had been cancelled after "Revelation of the Daleks", instead of being put on hiatus?
What if the series hadn't been put on hiatus after "Revelation of the Daleks"?
What if the character of Brigadier Lethbridge-Stewart had been killed off in "Battlefield"?
What if Sophie Aldred had died while filming "Battlefield"?
What if the series hadn't been cancelled after "Survival"?
What if Virgin Publishing didn't lose the Doctor Who license (or they never got it in the first place)?
What if they went with other ideas for reviving the series between 1989-1996?
What if the 1996 TV movie had led to a series?
What if Big Finish never existed?
What it "Scream of the Shalka" led to a revival, rather than what we got OTL?
What if Russell T. Davies hadn't succeeded in bringing the program back in 2005?
What if Christopher Eccleston had stayed for more than one series?
What if Christopher Eccleston had agreed to return for "Day of the Doctor"?