The new Big Little Lies theories that explain the mystery of Perry's brother.

SPOILER ALERT: This post contains big spoilers for Big Little Lies season one and the first few episodes of season two.

Perry Wright  was killed at the end of season one in Big Little Lies, but his presence continues to torment the Monterey Five a.k.a Madeline, Celeste, Jane, Bonnie, and Renata.

The physically abusive husband of Celeste had his known victims, but fans are speculating that there are probably more that we don’t yet know of.

Including his twin brother, Raymond. Well, potentially.

Watch the official trailer for Big Little Lies Season 2 below. Post continues after video.

Viewers of the HBO drama series only learnt that Perry (Alexander Skarsgård) had a brother when his mother Mary Louise (Meryl Streep) empathises with Celeste, telling her she knows the pain of suddenly losing a loved one, after she lost her five-year-old son Raymond.

“Right after the accident, right after we lost Raymond, I was sure I would not be able to go on,” she remembers.

“I was never sure about anything in my whole life, that I wouldn’t go on, but I did. Because of Perry.”

And now the show is no longer following Liane Moriarty’s novel of the same name, fans have a lot of new theories about what is going to play out.

Perry murdered his twin brother

One user posted to Reddit speculating that he believes Perry killed his brother when they were younger - a theory that seems to be popular among viewers.

"I feel like Perry killed his brother when they were children. Maybe while playing or something, his inner monster came out (maybe because his father physically abused Mary L. too). Just as we see in the twins [Max and Josh] now, how one of them is violent.

"Mary L. hid this fact and continued to love him and protect him as he was all she had left (as Perry’s father died too). He probably went through a lot of therapy and pushed this memory down and became a respectable man and married Celeste. But eventually, his true persona came out."

Veeeerrrrry interesting.

Mary Louise killed her own son

Posted to Reddit, one fan had a convincing conjecture.

"I think Perry got his power/abuse problems from Mary Louise. I think we’ll be shown that in the final episodes that she killed Perry’s brother in a fit of rage or something."

There was a great deal of support for this theory, with another user adding in support: "The way she yelled at the boys in the car in the first episode leaned me right into the idea that she wasn’t so gentle with her children."

What do you think about this Big Little Lies fan theory? Tell us in a comment below.

For more on this topic:

• There's a new Big Little Lies theory that spells danger for Celeste.
• The Big Little Lies and Mamma Mia fan theory that solves the mystery of Sophie's dad.
• The awkward first time Nicole Kidman met Big Little Lies author Liane Moriarty.
• Just five juicy fan predictions of what's to come in Big Little Lies season 2.