SPOILER ALERT: This article contains spoilers for the Netflix miniseries “The Perfect Couple” and the book by Elin Hilderbrand on which it is based.

Make way, Agatha: In Netflix's new murder mystery, "The Perfect Couple," it's been Abby all along.

The limited series, set during a lavish Fourth of July wedding weekend in Nantucket, began with the death of Merritt (Meghann Fahy), Amelia's (Eve Hewson) maid of honor. But why would anyone want to kill the maid of honor, you ask?

Well, money really is the engine of the world, especially for the wealthy families who already have it –– and, in the case of Abby (Dakota Fanning), those who marry into it. It’s revealed early on that Merritt was secretly pregnant from her affair with family patriarch Tag Winbury (Liev Schreiber), something his wife Greer (Nicole Kidman) quickly caught on to. But it’s not until the finale that audiences learn that a new addition to the Winbury clan is preventing Tag’s older sons from accessing their trust funds. That detail would certainly sting eldest son Thomas (Jack Reynor), who’s already millions of dollars in debt to his own mistress, Isabel (Isabelle Adjani). But ultimately, it’s Abby who’s willing to kill to put a bump in the road, with detectives discovering that she drugged Merritt before drowning her during a late-night swim.