Since Netflix Hasn't Told Us Who Killed Sara? We'll Give You Our Theories

At times, Mariana seems as if she's simply been corrupted by César and is only following his lead. The flashbacks tell a different story, as we see Mariana learn that Sara is carrying César's child. The pair then go on a walk where Mariana contemplates pushing Sara off a cliff before ultimately conspiring with Elroy to get rid of the girl. It is Mariana who suggests Sara try parasailing and Mariana who hands the knife to Elroy in the hopes he'll tamper with the harness.

We don't know if Elroy actually used the knife but we do know that Mariana cleaned up the scene of the crime and pretended to call an ambulance for Sara. It's also hinted that Mariana murdered Elroy as he lay in the hospital so that the truth would never be revealed. She certainly has a strong motive for being the killer, seeing as Sara was messing around with her husband and dating her son, but could she also be innocent? She's not the only Lazcano with a reason for wanting Sara dead.

Who Killed Sara? isn't saying outright that César killed Sara, but they've certainly implied it. César's the one that talked Alex into taking the fall for the Lazcano family when Sara was first killed and it is César's baby Sara was pregnant with at the time of her death. The only person César looks out for is himself. That's clear from how he treats his family and the women he sleeps with.

We already know that César feels he's above the law, due to the criminal comings and goings at his casino and the brutal murders that happen there at the hands of his colleague Sergio. He also knew that Sara was pregnant with his child and likely knew more than she let on about the sinister nature of his casino. In one of the final flashbacks of episode 10, we see César shoot someone but it's unclear if it's Sara. We also know in the present day that a skeleton with a bullet hole is uncovered in Alex's yard. Could it be Sara? He does tell others he's not a killer but he's also a liar so what are we to believe.

We still don't know much about Nicandro, other than the fact that he'll be making his debut on season two. In the trailer for the upcoming season, Alex is shown asking about him, but not much else is revealed. However, when we spoke to Manolo Cardona back in April, he teased the arrival of "a very important character." Could he have been referring to Nicandro? And if so, is he the one behind Sara's murder? Guess we'll find out soon enough.

The biggest twist of all might just be that Sara is the killer. Towards the end of the season, Alex discovers Sara's notebook hidden away in a wall. Her writings and scribbles detail Sara's battle with depression and suicidal thoughts. Sara also stole a tape of Sergio murdering Flor, hiding it with her friend Marifer as insurance against any possible retaliation from César or Sergio. Sara knew César was dangerous and he didn't take news of her pregnancy well, leading to her eventually becoming paranoid and suicidal.

Alex is led to believe that Sara died as a result of the parasailing accident, but that might not actually be the truth. When Alex discovers Sara's journal, he calls Elisa to let her know they've been wrong about everything. Then there are the flashbacks of a woman being choked and César shooting the gun. Did Sara ask for someone else to end her life because she couldn't bare the mental anguish and trauma she'd been through in relation to César's dirty dealings? Here's hoping Netflix gives us answers in season two.