If your interests run to thaumaturgy, the Eleusinian mysteries, Grand Guignol and the darker side of carnival (and I know you're out there), then BATS theatre has the show for you. It's called Demeter's Dark Ride - an Attraction, and while it only has two more nights to run, there are four shows each night (at 7pm, 8pm, 9pm and 10pm) so you still have a few chances to catch and be caught by this otherworldy experience.
Be warned: this is not a conventional theatrical show, but a guided tour of the underworld. It is unsuitable for claustrophobes, achluophobes and arcanophobes, and you should be prepared for a complete pan-sensual discombobulation. The theatre has been transformed inside and out, and you will be led into the back passages and forbidden regions of this mysterious building. If nothing else, you should see it for the chance to sate you curiosity about those signs pointing to the Royal Antediluvian Order of Buffaloes.