homicidally

Ismay and Heather share a festering secret that poisons more than one relationship in this London household before seeping out and infecting all the neighbors — including the homicidally inclined Marion and her abominable brother, Fowler, who have made a career of preying on the love-starved.

[A]senic use was widespread. Not that we have a reliable test for it, it is not much used, homicidally.