I think one of the reasons why this story always seems so fresh and exciting to me is the approach it takes to its chosen era. Although the Trojan wars have generally been treated as the stuff of hallowed and ancient heroism and wonder, this story deliberately brings the participants down to Earth. Hence the characters who are supposedly motivated by martial self-importance constantly indulge in petty sarcasm, self-pity and cowardice, showing their all-too human sides.

For instance, when Steven confronts Paris, the latter keeps descending into anachronistic little asides to the former ("Yes, well I'm prepared to overlook that for the moment...Yes, well, personally, I think this whole business has been carried just a little bit too far. I mean, that Helen thing was just a misunderstanding...To be a prisoner of war is considered very bad form"). Indeed Paris is openly derided even by his own family as being, in military terms, a joke, and his boasting at having captured "Diomede" (Steven's assumed identity) is clearly presented as absurd and convincing no-one.

Similarly, King Priam, though seemingly wise, and undoubtedly benevolent, has a rather fussy bumbling quality, and he manages two inadvertent verbal slip ups when addressing Vicki, first when promising she'll die when he says and not before (which elicits a charmingly wry "that's very reassuring" from Vicki as Priam goes on to admonish the others for not knowing how to handle children), and later when musing on what a shame it is that Paris couldn't fall for someone "sensible" like her instead of someone with "good looks". He even seemingly neutralises the apparent threat of being consigned to the dungeons by remarking how he sometimes likes to spend the odd hour relaxing there.

Menelaus is petulant and weary about the wars and desperate to get home, responding to Agamemnon's appeals as to the cause with "Quite frankly, no...it makes me a laughing stock". He is also highly taken with the first part of the Doctor's plan - setting off in the fleet from Troy - but less so with the second part - returning under cover of darkness.

This sort of grandiosity-bursting artistic approach - allowing ordinary human pettiness to undermine power fantasies - is similar to a style employed by many British humourists, as seen in Monty Python, Douglas Adams and Terry Pratchett, to name just a few examples, celebrating ordinariness above pretences to glory.

The romance between Troilus and Vicki (or Cressida as she ultimately becomes) feels rather less genteel or stilted than that between Susan and David in her departure story (interesting to note that the same sort of "coming of age" motif is being used here too, the companion effectively completing the journey to adulthood by dint of being paired off romantically). This may partly be because they are closer to each other in age. It feels more like a fumbling adolescent first love for them both, and the way in which Vicki sees through the pretensions to military swagger in his nature, connecting with his more vulnerable and childlike side, which he is trying to conceal, is very touching. It draws them together believably. Similarly, the way in which she tricks him into leaving Troy by persuading him that he has a chance to prove his military prowess is psychologically clever. Vicki/Cressida is exercising her protective, nurturing instinct while at the same time leading Troilus to believe she accepts his capabilities as a warrior. Of course she later admits to him that she would never have sent him out if she'd thought there was any danger.

Odysseus is not depicted very flatteringly here. Throughout the story, he is cruel, cynical and sarcastic, not treating the Doctor particularly reverently even when it is still thought possible that he might be a god. The Doctor's own outburst to him, after he has been coerced and threatened by Odysseus throughout most of the story ("You're selfish, greedy, corrupt! Cheap! Horrible!"), is not only understandable in context (and is a nicely played bit of anger from Hartnell too) but even more appallingly apt considering the events at the climax.

Cassandra's predictions of woe (culminating in the, to me at any rate, marvellously "Up Pompeii"-esque "It's a bit late to say 'Woe' to the horse" from Paris) are ultimately vindicated, and it must be said that after the preceding lightheartedness, the events we are shown are truly horrible, with Priam and Paris both killed, and Casandra "saved" for Agamemnon (a term with very disturbing implications). This is a city which is completely destroyed, and although the story seeks to end on a note of optimism with Troilus and Cressida, it's difficult not to feel uneasy when remembering the Doctor's role in this. He is, after all, the agent of deliverance of all this carnage, even if under duress. His contemptuous dismissal of Odysseus, jeering that he can have his "insignificant win" is clearly an indication of his far wider perspective, but I do wonder whether something like this isn't destined to be on his conscience subsequently.

There is also a new companion to replace Vicki, Katarina, but she isn't even introduced until the last episode, and has few lines, with little chance to make an impression at this stage. The most significant aspect of her character so far is the way she translates everything about the Doctor and the TARDIS into terms of reference that make sense to her. Hence she believes the Doctor to be a god, and his ship part of a celestial journey to the Great Beyond, or afterlife.

All of the three established regulars do well here. Vicki demonstrates that she can take care of herself, and the Doctor obviously has enough faith in her to accept her reasons for leaving. Maureen O 'Brien turns in an engaging and enthusiastic performance (whatever her private feelings about the role may have been, she played it enjoyably in my opinion). Peter Purves gets a few fight scenes and the chance to react to Vicki's romance (although he seems more amused than jealous to me). And William Hartnell handles both the humour and the gravity of the last few scenes (Vicki gone, new passenger aboard, Steven wounded) with apparently effortless confidence.

I find the story a very rich and engaging one, with strong characters, and a plot which manages to change gear between self-aware humour and relatively grim drama with surprising ease. One of my favourite Hartnells.