Hold on tight, “How to Get Away with Murder” fans. After an explosive freshman season, ABC’s new drama is coming to a close on Thursday and wrapping up a major mystery: Who killed Lila Stangard?

Those that have been following the series will remember that Middleton University student Lila Stangard turned up dead at the beginning of the season. Lila’s boyfriend, Griffin O’Reilly (Lenny Platt), and friend, Rebecca Sutter (Katie Findlay), were accused of the crime. Campus professor and lawyer Annalise Keating (Viola Davis) was tasked with proving Rebecca’s innocence. With the help of her law students – Wes Gibbins (Alfred Enoch), Connor Walsh (Jack Falahee), Michaela Pratt (Aja Naomi King), Asher Millstone (Matt McGorry) and Laurel Castillo (Karla Souza) – Annalise managed to clear Rebecca’s name. However in the process, Annalise’s husband, Sam Keating (Tom Verica), was accused of the crime and murdered after it was discovered that he had been having an affair and impregnated Lila.

But did Sam really kill Lila? The Season 1 finale of “How to Get Away with Murder” will reveal the truth.

Wes has been growing suspicious of his new girlfriend, Rebecca, and doubting whether Sam was guilty of killing Lila. After receiving a letter addressed to the previous tenant of his apartment, Rudy, Wes began to suspect that the mysterious former student could hold an important clue. Wes and Laurel discovered that Rudy was confined in a mental hospital … and was admitted right around Lila’s murder. Visiting Rudy, the pair showed him a photo of Rebecca. He only had one thing to say: “wet.”

What could “wet” mean? Wes and Laurel believe that Rudy was revealing Rebecca’s involvement in Lila’s murder. The pair don’t have any concrete facts to pinpoint Lila’s death on Rebecca, but she’s beginning to look guilty – and tracking Wes to the mental institute is not helping her case.

Is Rebecca guilty? It’s definitely possible, although naming Rebecca as the killer seems too easy for such a twisted show. Fortunately we’ve got a couple of other theories:

Rudy – Rudy’s obviously experienced something traumatic to end up locked up. He could have been responsible for killing Lila … or he could have been an accomplice. Since Rebecka already successfully manipulated Wes, we have no doubt that she could have done the same for Rudy.

Griffin – Maybe Lila’s boyfriend did kill her. The police seemed to think Griffin was guilty, and they could be right.

Annalise – This is a stretch, but what if Annalise was lying to everyone? One theory is that Annalise discovered Sam’s affair with Lila and decided to take matters into her own hands. Although it seems odd that she would get involved in the trial, she could have just been trying to cover her tracks and stay involved in the case.

Frank – Frank (Charlie Weber) seems to be willing to do anything for Annalise … but what about kill? He could have helped dispose of Lila’s body. Frank also has a history of dating students. Lila could have been one of his hookups and things may have spiraled out of control when Sam got involved.  

Bonnie – Bonnie (Liza Weil) had a weird obsession with Sam. It’s possible that Bonnie could have found out about Sam’s affair and took out her jealousy on Lila.

According to the synopsis for the two-hour finale, a series of flashbacks will “piece together what really happened the night of Lila’s murder.” Wes and Rebecca will “continue to grow suspicious of each other.” Meanwhile, “Wes, Connor, Michaela and Laurel may have dug themselves in too deep of a hole for Annalise to save them.”

The Season 1 finale of “How to Get Away with Murder” will kick off on ABC at a special time, 8 p.m. EST. Who do you think killed Lila Stangard? Tweet your thoughts to @AmandaTVScoop and take the poll: