Not a terribly polished idea but welcoming ideas:

Does anybody want to join me for a threaded murder mystery ala' Clue? (Any other ideas welcome?)(Also known as Jen has trouble feeling enthused about Anthea and wants to give her muse a kick up the a$$ and as her muse loves Agatha Christie/Hercule Poirot etc. I'm going to see if this helps)

Setting: A routinely organised cards game ends in disaster when one of the guests goes to check on the host and finds him dead and the manor in a magical lockdown until a certain condition is met (murderer caught or like a panic room the key is found to allow them out)... (potential trippy plot-twist that has occurred to me is that host actually owes a ton of money to the participants and is trying to either a) frame one of them or b) fake his own death.

I think it would be fun to come up with motives that others can create that may or may not be true to accuse each other of.