It's been a mystery which has plagued them for months, but Marisol (Ana Ortiz), Carmen (Roselyn Sanchez), Zoila (Judy Reyes) and Rosie (Dania Ramirez) will finally figure out who was responsible for both Louis and Blanca's (Naya Rivera) murders on Devious Maids. 

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In a preview clip for the season three finale, the women have finally put together one big piece which could solve the entire puzzle when it comes to the two murders-and it could lead to the most unexpected arrest for murder yet.

"We think Louis was murder at the Stappord's house and that Blanca found out about it," Rosie says to Carmen in the clip.

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"When did we become maids who solve murders?" Carmen asks.

However, the fact that Marisol and Rosie were able to test the shocking stain on Taylor's (Breanna Brown) couch and have determined it is blood-likely Louis', could point the finger at Michael (Brett Cullen) as the murderer, leading to an unexpected arrest that no one saw coming.

"You have the right to remain silent," detectives say to him in the clip.

However, the maids could still have been very wrong with their investigation-and as a result one big attack could happen with the killer, as he surfaces at Evelyn (Rebecca Wisocky) and Adrian's (Tom Irwin) house and appears to take them and Carmen hostage-and could kill someone in the house in the pursuit to make sure the secret of their crimes is never revealed.

Devious Maids airs Mondays at 9 p.m. on Lifetime.

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