Cheap and quick- how to cover 5m long x 2.5 m high bookcases for a kids party?

[teslagirl]

Doing a Halloween party at home. We have said Ikea bookcases filling one wall of the living room. 75% of the box areas are filled with the DSs' toys. Keen not to have the 'party' turn into a 'playdate' with all the toys pulled out so want to isolate the bookcases, but how- in a 'Halloween-ish' way?

I'm happy to gaffer tape The Solution to the top of the cases as long as tape is strong enough for the weight.

My thoughts are gaffer tape butchers paper to it- but a) I'd have to decorate the paper (+ costs, + time involved) and b) where to get that amount, bearing in mind I don't have THAT much time!

OR buy muslin and shabbily dye it. BUT I bought some today for a different project at 3.99m for 150cm wide which I thought a bit expensive- that'd be 30 quid.

Wish I could get sheets of grey plastic- one probably can- but from where and how much? I'd draw a brick wall design on that but how long might that take?!

Any ideas?

what about an old white sheet draped over with ghost figues on done in fabric paint?

lining paper? it's about £1 a roll but don't know how much that would translate to.

A combination of the above. Lining paper/ newspaper cut out in ghost shapes and pined on back of white sheet drapped over bookcases. Put a table lamp on one of the bookcases to backlight the blocked out ghost shapes to make a spooky look. Quick and really cheap.

Great ideas, team! Thanks