Prologue: 'Murder in the Ballroom'

Zakou went rigid in his seat, pain twisting in his stomach as he felt bile rising up in his throat. He coughed, doubling over in pain as he wiped his mouth, the dim light revealing dark red blood.
"Poison..." He mumbled, seeing his now spilled drink, as blood dripped from his mouth.
He looked up weakly, seeing he was suddenly alone in the panic room, as he drew his last breath.
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An after party, starring a murder, with four suspects. One night to figure it out.