The exhilarating revelations during the penultimate episode of "Orphan Black" season 3 kept viewers talking about it for days and thinking about how the season finale will beat all the events that happened in the previous episode. 

In "Insolvent Phantom of Tomorrow," it was revealed that the Castor original, as well as Leda's, is one and the same person. But the more surprising fact that was uncovered during that episode was Sarah (Tatiana Maslany) and Felix's (Jordan Gavaris) foster mom Mrs. S (Maria Doyle Kennedy) is the main source of both clones.

It was revealed that Mrs. S is actually Kendall Malone. She is a chimera with two cell lines, which means that she absorbed her supposed male twin while she was in her mother's womb. Is this the reason why Mrs. S decided to take Sarah and her daughter Kira (Skyler Wexler) in her care for their protection? 

Fans are expected to find out the answers to this question, as well as Mrs. S's real connection with The Dyad Institute, in the season 3 finale of "Orphan Black." But will the series unveil the truth next week? 

The official synopsis for the "Orphan Black" season 3 finale titled "History Yet to be Written" reads:

Castor (Ari Millen) and Topside force Sarah to make uneasy alliances. But there is some rest for the wicked, when Donnie (Kristian Bruun) gives Helena an unexpected 'gift', and the results of Alison's candidacy finally come in. Even as team Leda takes a moment to breathe, change is afoot and a life hangs in the balance." 

Also, viewers of the critically acclaimed Canadian sci-fi series would like to find out if Helena will face the consequences of her bloody encounter with the drug dealers, as well as Grace's (Zoe de Grand Maison) betrayal just to be with Mark (Millen) in the final episode of the season. 

The season 3 finale of "Orphan Black" airs Saturday, June 20, on BBC America.