Dexter's original series finale was famously controversial. However, several seasons before the serial killer drama's conclusion, another contentious ending rocked its audience. The events of the Dexter Season 4 finale aggravated more than a few viewers -- for understandable reasons. Dexter's kind-hearted wife Rita Morgan (née Bennett) was murdered by the most notorious villain ever to appear in the Showtime series.
Source：https://www.cbr.com/dexter-why-rita-murdered/
