The winter finale of How to Get Away with Murder left fans speechless. After waiting weeks to learn who was under the sheet, it was revealed that it was Wes who's now dead. However, in a twist, it was also revealed that it wasn't the fire that killed him. So how did Wes die on How to Get Away with Murder? Unfortunately, it'll be a while before fans know the truth about his demise, but for now many are just angry that Wes is dead at all.
After the Season 3 premiere, each passing episode of the season revealed who wasn't under the sheet thereby narrowing down the list of possible characters that could die in the mid-season finale. At the end of Episode 7, fans saw Wes with two detectives, which seemed to indicate that Wes was safe, however, this was obviously not true. One could argue that the previews for that particular episode only said that the traitor would be revealed and not necessarily that the person would be safe as well, but since every episode leading up to that one revealed who was not under the sheet, it made sense that many viewers thought he was in the clear.
However, amongst their devastation, fans are already theorizing not only how Wes could've been killed, but who could've killed him. Based on how badly burned Wes was, it's hard to guess what the actual cause of death was since it was revealed it wasn't the fire itself. But I can guess who did it. In my opinion, the most likely suspect is Frank. Bonnie had asked him to do something when Annalise realized the DA was investigating her and although it seemed like Bonnie just wanted Frank to turn himself in, it may have led him to another conclusion. Maybe Frank and Bonnie knew it was Wes who had turned on Annalise somehow and they figured if they got rid of him, the DA wouldn't have as strong of a case.
Another suspect is Nate. Fans did see him go into the house before Laurel and right before it blew up. However, Nate doesn't seem like a cold-blooded murderer and if he really did kill Wes, why would he go to the coroner to confirm the cause of death? Wouldn't he already know?
Honestly at this point it's anyone's guess who killed Wes and why — or even how it was done in the first place. Unfortunately, fans will have to wait until January to get any real, concrete answers.