Dr. Who go back in time.

I would suggest to start with the 9th doctor, which start the new version of the show

I'd start with the first season of the 2005 reboot, the newer format is a lot more accessible than the old school series.

Before I knew about Doctor Who, I was watching Doom Watch.

Zee-Zee once suggested "The Bells of St. John" (s07e6) which probably would work.

I myself started (inadvertently) with "The Eleventh Hour" (s05e01) and found it easy enough to follow...

(Edit: Both are from the new series)

Horror of Fang Rock featuring Max Headroom.

If you want a sampling of classic Who, The Five Doctors is a great episode. (That’s what I started with.) It introduces several regular characters, it involves a lot of elements that are staples of the Who universe (Daleks, the Timelords, et cetera), and it’s not tied to any broader continuity.

If you watch The Five Doctors and don’t like any of what you see, you may want to try the new series... in which case I'd recommend The Empty Child, a wonderfully creepy episode from the first season back on the air.

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Also, I'd like to point out that a Pokemon Time Lord in a Doctor Who diaper is pretty much the perfect encapsulation of the furry community. So props for that ;)

Tom Baker's pretty good.

I love that you did a diapered charizard pic. I like seeing the tough looking fire pokemon padded in a crinkly diaper.

The best way if you're a newcomer to this is to start with the 2005 revival series, The Ninth Doctor Season (Eccleston). Continue on with Tennant, Smith, and the current one. If you survive all of them, then consider giving the classic ones a watch afterwards (Pertwee and Baker). Personally, I recommend the Troughton episodes. At least the ones that are available to the general public.

As cute as this is, some streams don't feel right to me when they cross for a variety of reasons.