Teenager, Joan gets more than she bargained for when her workaholic dad buys her a cute pet monkey who grows wings, fangs, and an insatiable thirst for blood come nightfall. 十幾歲的瓊，當她工作狂的爸爸給她買了一隻可愛的寵物猴子時，她得到了比她預想的更多的東西，這隻猴子長著翅膀、尖牙，在夜幕降臨時，她對血的渴求永不滿足。
A celebrated author's story about a genetic experiment morphs into reality, when it is read by three strangers. Trapped in a room, the four discover that one of them must be killed to save the rest from an escaped undercover recruit.
