她写了一部关于一个残忍的连环杀手的惊悚小说。

She wrote a thriller about a brutal ___serial killer.

警方正在追踪一个已知的连环罪犯。

The police are tracking a known ___serial offender.

这些图像因与连环杀戮有关而被扣留。

These images were withheld because of their connection to ___serial killings.