Marco Polo

DOCTOR: Oh we're travellers yes. That's my grandchild, Susan, and that's Miss Wright, and that's Charlton.

MARCO POLO: Susan's a bad influence. 
(Never a truer word spoken) 

DOCTOR: I could hardly have it placed in the hanging garden, now could I? What does he think it is? A potting shed, or something?

MARCO POLO: Ian, don't you see it doesn't matter to me why you lied. What is important is the fact that you are capable of lying.

KUBLAI KHAN: Your beloved husband-to-be, so anxious to be worthy of your love, drank a potion of quicksilver and sulphur, the elixir of life and eternal youth, and expired.

DOCTOR: I always knew Tegana was a two-faced villain.

(Well duh, Doctor) 

Points of Interest 

• I know the TARDIS has always had various problems throughout the 48 years of Doctor Who, but I hadn't taken in just how rickety it is right at the start. In the Daleks it doesn't work because one small part is (very easily) removed. There are no spares for this extremely vital part! In the Edge of Destruction a switch gets stuck, which nearly causes the whole ship to explode. And now here in Marco Polo, for no reason that is explained, the lights and heating have failed and there's no water, turning the ship into what would have been a death trap if Marco Polo hadn't conveniently chanced upon them in exactly the right place and time in this absolutely gigantic part of the world. 
• Where does Susan's 60s girl lingo come from all of a sudden? "Oh, crazy", "I dig it" and all that. It's like she's saying that just to annoy poor old Ping-Cho. No wonder when Susan offered at the start of the story to go and find fuel with Ian and Barbara, Ian very firmly told her to stay with the TARDIS! Or "TARDIS", I should say, since the "the" hasn't been invented at this point of the show. Oh, and Susan's scream at the cliffhanger to Five Hundred Eyes is her most annoying so far. An impressive feat. 
• Much as I adore everything about this story, Tegana seems very indecisive in the second episode. He makes a big thing in the cliffhanger for the first episode about getting poison and using it in all but the first water gourd. So what happens when they head out into the desert? He doesn't bother with the poison, he just slashes the gourds. That seems a more sensible plan anyway, so what was all the guff about the poison for? 
• The episode titles are wonderful. As is Tristram Cary's soundtrack. That is all. 
• John Lucarotti really does blend the educational aspects into the story brilliantly. The stuff about water boiling at a lower temperature when there's less air pressure, all of that about the Hashishins (and the brilliant messaging system the Mongols used), and bamboo exploding and so on. To be honest, I'm slightly less convinced about condensation, mainly because of Ian's rubbish explanation. "The outside of the caravan cooled, but the inside stayed warm, and so moisture formed on the inside. It's condensation, we just call it that. It's just a name". Yeah, good going with that, science teacher. I bet your pupils learnt loads from you.  

Verdict

It's the first true classic for me. What makes Marco Polo especially fantastic is how unique it is. The rambling journey over a period of months through one of the most interesting periods of the world's history. It uses the seven episode length to give it that epic feel. While it's not quite a Marinus-style different location/enemy every week story, there is certainly an element of facing fresh and new dangers with each episode that keeps the story fresh and exciting. This story is where Doctor Who really hits its stride. When you have the Lucarotti/Hussein combination that isn't particularly surprising. The regulars are all in top form, and Eden, Nesbitt and Merten provide so much depth to their characters. It's a story I will always cherich and enjoy whether I get to see it or not. It shows just what a great show Doctor Who is that on my last marathon Marco Polo only managed 12th place.