Doctor Who is probably one of the best Science Fiction shows ever made. It's got action, romance, moral struggles, clever writing, and superb acting. And the special effects are just good enough. =)

If you're a fan of SciFi in general, I'd say just start with Series 1 episode titled "Rose", featuring the 9th Doctor, and aired in 2005.

However, if you only have a casual interest in SciFi and not sure if Doctor Who is for you, I recommend first starting with a couple of the best episodes:

• "Blink" Series 3 (2007), featuring the 10th Doctor. This episode is by far the most clever writing of any SciFi involving time travel. Ironically, the Doctor isn't really featured in this episode. So it's not really typical of the series. But it's well worth watching.
• "Vincent and the Doctor" Series 5 (2010), featuring the 11th Doctor. This is probably my next favorite episode. It's a hugely touching story involving Vincent van Gogh. If you don't cry a little at the end, you're one heartless individual.

At this point, you've got a decision to make. Start at Series 1 with the 9th Doctor. Or start at Series 5 with the Eleventh Doctor.

Series 1 starts out with a bit of a darker tone (seems like every few episodes is dealing with some sort of big ancient evil) and because they weren't sure how popular the series was going to be, the special effects budget wasn't that large.

Series 5 story centers more around the Doctor's traveling companion Amy Pond, and has a bit of a fairy tale feel to it while staying within the bounds of the Doctor Who universe.

Because of the way the show is structured, you don't really have to be fully immersed in previous episodes in order to enjoy the series. So if you like it on the lighter side, I'd say stick with Series 5. However, if you did want to fully appreciate just how old the Doctor is, what certain things means to the character (they sometimes do make allusions to big events in his life... like Rose), and the amount of compassion and personal struggle he deals with, then Series 1 is the place to be.

Here's a brief intro to the Doctor, just so you're not completely lost. He's an alien, the last of a race called the Time Lords. And they have a way to cheat death by "regenerating"... Regenerating doesn't come without cost, though... He's still technically the same person and has the same memories, but his entire personality, appearance, character, and tastes totally changes. It has the side-benefit, of course, that the Doctor can outlast any of the actors that play him.

There's a lot more I can go into... But suffice it to say, Doctor Who is a fantastic series and you should go watch it now! It's available on Netflix and Amazon Prime.