*Warning: This article contains spoilers for Chambers Season 1*
The heart comes to her courtesy of Becky LeFevre (Lilliya Scarlett Reid) whose mother (Uma Thurman) and father (Tony Goldwyn) are mourning their daughter's untimely death.
But how exactly did Becky die? It turns out to be more complicated than it initially seems.
So, how did Becky die?
As soon as Sasha receives the new heart, she feels like something is off and like she can still sense Becky's presence living inside of her. This causes her to dive deep into the mystery of her heart's previous owner and what brought on her premature death.
It turns out that Becky died after being electrocuted in a bathtub. While bathing, an old radio fell into the tub, which caused Becky to become electrocuted. However, we later find out that there's more than meets the eye and that the tragic accident was not actually so accidental after all.
In fact, Becky's death was a suicide. She plugged her bathtub so that it wouldn't drain and then purposely dropped the radio in with her so that she'd be electrocuted and die as a consequence. Her best friend's boyfriend, Ravi (Jonny Rios), whom Becky had been secretly sleeping with witnessed her death.
Why did Becky kill herself?
Here's where it gets more complicated. Sasha senses that there's a dark backstory surrounding her new heart and thanks to Becky's parents' scholarship, enrolls in the same high school Becky attended. There, she becomes more curious about Becky, whom other students mention Sasha reminds them of.
When she appears to be a prodigy at fencing, like Becky was, without ever having practiced the sport, Sasha delves deep into Becky's story and becomes obsessed with uncovering what led Becky to take her own life. When she takes the psychedelic DMT, things become a bit clearer.
While tripping, Sasha learns that Becky was the chosen vessel for Lillith, a demonic mythological first wife of Adam who Becky's parents (and their cult, The Annex) absolutely worship and revere. We go on to learn that The Annex's sole purpose is actually to find a human host for this Lillith demon.
Since Becky was born on March 21, the same day of the ritual that invites Lillith to find a body to live in, she became the demon's host. Granted, Becky doesn't know she's hosting Lillith because the rituals of the event were so traumatic, she completely blocked them from her memory.
At first, it seems like housing the demon is a positive: Becky makes a ton of new friends and begins to excel in school. However, she soon notices a darker side manifesting as she becomes meaner and more violent toward her peers and family, one time even causing bodily harm to her friend Penelope.
Troubled by what's happening to her, Becky experiments with ayahuasca, hoping that the hallucinogenic drink will give her some insight into her past. During her trip, Becky unlocks the traumatic memory of the spring equinox ritual and discovers her parents and high school counselor were responsible for having Becky play host to the Lillith demon.
Horrified by the discovery and by the many forces within her, Becky decides to kill herself to put a stop to this demon. But when she dies, her heart keeps beating, and Lillith reaches out to a new host, which likely causes Sasha's heart attack.
This is why Becky's parents are so welcoming of Sasha and why they keep such close tabs on her even after the heart transplant's been completed. The whole backstory of The Annex also explains why we're told to "Watch out for that family" in the trailer.
Stream Season 1 of Chambers on Netflix now.