Y'know, if this had been just the tiniest bit less S24-shoestring-budget ropy, it'd be hailed as a Seven-era classic. It's very clearly one of the first products of Cartmel's commissioning, and the script has got plenty of ideas even if they don't quite gel -- I never picked up on it as a kid, but watching it now, it's almost too obvious the way it's all about metamorphosis and change (I mean, come on, Delta) linked through the ideas around insect life cycles. It's just a little bit undercooked, really -- in particular, the Billy/Delta plot doesn't get enough screen time and so we don't get enough motivation for everything that ends up happening (and it kind of leaves you wondering whether she's using Alien Insect Queen Sex Pollen Equivalent on him, which I don't think is the intended effect).
There are actually a lot of things in it that are somewhat reminiscent of Cartmel's last PDA, Atom Bomb Blues, which makes me think he possibly had quite a big influence on the script -- either that, or the script influenced him. Also, Seven's very cute in it -- the bit in the TARDIS in episode one where he rescues the bus is lovely, as is him dealing with Ray and her emotional problems despite being clearly out of his depth (fandom's always "I wish we'd had Ray instead of Ace" but you know what I want? I want AU fic of "Ray joined and then Ace joined in Dragonfire too
Its biggest problems are the acting (though Ken Dodd isn't nearly as bad as fandom paints him, different sections of the guest cast seem to be coming at it from completely different points of view -- is this a lulsy period comedy with Hi-de-Hi overtones or a dark story about interplanetary genocide?, and the thing is it is kind of both) and that the cliffhangers are utterly, utterly contrived -- even more so than the meta-cliffhanger coming up in the next serial. Incidentally, though, Mel doesn't scream at the baby; she screams at the weird metal thing belonging to the alien woman who's been brandishing guns at her until about two seconds ago suddenly starting to open. As soon as the (cute but surely too big to fit in that egg) baby appears she stops screaming. Is this a fandom myth or a sly bit of post hoc editing on the DVD?
I watched Twin Dilemma at the weekend too, incidentally (my last ever Colin-I'd-never-seen-before) but I'm still wrapping my head around what I think of that. (Well, except that I want to know where all the Four/Azmael that-time-by-the-fountain slash is, fandom. Does everyone hate this story so much that they don't get inspired by the incredibly obvious stuff?)