Cryptic crossword No 818

Hi all - sorry for having deserted MyCrossword for so long: been distracted by other things (like finishing off the novel I'd been writing). But here you are - have fun! Yep - one of my infuriating 'long-'uns' here... There is a mini ghost theme and some knowledge of it might help in solving that same long clue - but my tester said it'd probably be OK for most people.

And a heads-up (OK - shameless self-promotion!): I'm making my debut appearance in the Independent on Sunday (13th). That one also has a theme - probably easier to spot than this one. Enjoy!

Thanks Laccaria, and congrats on upcoming debut! Lots to enjoy here - particular faves include 10a, 11a, 16a, 17a, 13d 4d & 21d. Spoilers ...

Thanks for the lovely puzzle Laccaria, a satisfying solve. I particularly liked 11a (neat), 17a (fun), 25a (likewise), 28a (neat), 29a (clean), 3d (fun), 7d (neat), 13d/4d (smooth assembly, nice surface), 18d (neat), 20a (likewise) and 22d (likewise)

Bravo, Laccaria, enjoyed this a lot. The PDM for the long one brought a big smile to my face (knowledge of the theme definitely useful) - and of course now I remember you saying a while back you were planning to do this theme. Lovely stuff. Faves were 17a, 28a, 21d.

I don't know the theme well but enough to recognise some allusions and the long 'un, Laccaria. Thanks for putting this together. 16a, 17a, 29a, 3d, 13d/4d, 21d and 22d were my favourites. Many thanks. PM