The mystery surrounding Peri's (Mariana Klaveno) killer will unravel in the penultimate episode of "Devious Maids" season 4.

According to the synopsis for the episode, titled "Much Ado About Buffing," Marisol (Ana Ortiz) will discover something from Genevieve's (Susan Lucci) past that may be linked to the information about the person responsible for Peri's death. Will they finally catch the killer soon?

Meanwhile, the trailer for the upcoming episode shows a touching moment between Rosie (Dania Ramirez) and Spence (Grant Show). Rosie will visit Spence behind bars, but the daytime opera star might be losing hope that he could still get out of prison. However, Rosie will not give up on her husband, and she will reassure him that she will get him out of jail as soon as the real killer has been found.

A light moment is also featured in the trailer, when Evelyn (Rebecca Wisocky) catches Adrian (Tom Irwin) in a compromising position with her former friend Gail (Julie Claire). But Adrian will deny that something is happening between them, even if his pants are already dropped to his knees.

Zoila (Judy Reyes) will also make sure that her relationship with Kyle (Ryan McPartlin) is smooth-sailing despite the demands of her job.

The synopsis for the episode reads:

"Marisol will end up learning a secret from Genevieve's past that may provide a clue to finding Peri's killer. Zoila is going to struggle to balance her love life and her demanding new boss, while also helping Rosie investigate The Circle. Danni (Sol Rodriguez) will appear to be warming up to Carmen (Roselyn Sanchez), but her motives won't be so pure. Spence is going to help Rosie when Miguel (Alejandro Vera) begins to act out at school."

"Devious Maids" season 4 episode 9 airs on Monday, Aug. 1, on Lifetime Network.