Like an episode of Jonathan Creek… but I quite liked Jonathan Creek when I was kid.
Not really sure how this is running a 12 from the BBFC, though
★★★
Frederick Loren has invited five strangers to a party of a lifetime. He is offering each of them $10,000 if they can stay the night in a house. But the house is no ordinary house. This house has a reputation for murder. Frederick offers them each a gun for protection. They all arrived in a hearse and will either leave in it $10,000 richer or leave in it dead!