как это переводится?

The party was in full swing when the light grew dim. However it was typical for Halloween. But when the light appeared again, everybody saw a man with a knife in his back lying on the floor. Was it a Halloween joke? May be. And may be not.
For two young people such jokes turned into a real nightmare. To their horror they found out that some of the guests at the fancy-dress party was a murderer.
Не пользуйтесь переводчиками. Получается полнейшая чушь.

The party was in a full heat when light has died out. However, it in spirit of a Halloween. But when light has appeared, on a floor the person with a knife in a back laid. A joke in spirit of a Halloween? Can be. And can, and is not present.
For two young men similar шутк have turned to a nightmare. To horror, they have understood, that someone from present on a party in suits-murderers.

The party was in a full heat, when погас light. However, it in spirit of a Halloween. But when light зажегся, on a floor laid the person with a knife in a back. A joke in spirit of a Halloween? Can be. And can, and is not present.
For two young men similar шутк have turned to a nightmare. To свому to horror, they have understood, that someone from present on костюмированной to a party the-murderer.

вот это было переведено переводчиком. советую завести переводчик PROMT