The Big Little Lies and Mamma Mia fan theory that solves the mystery of Sophie's dad.

One of the biggest cinematic mysteries of our time has been solved and we owe it to the latest season of HBO’s Big Little Lies.

And by this, we mean we finally know the identity of Sophie Sheridan’s (Amanda Seyfried) father in Mamma Mia!.

Let us explain this in three very detailed steps:

Watch the official trailer for Big Little Lies Season 2:

Step one:

This season of Big Little Lies stars the legendary Meryl Streep as Mary Louise, the grieving mum of dead Perry, who is conveniently played by Alexander Skarsgård.

Step two:

In real life Alexander Skarsgård is the 42-year-old son of Swedish actor Stellan Skarsgård.

Step three:

Stellan Skarsgård plays Bill Anderson in Mamma Mia!, the one-time lover of Meryl Streep’s character Donna Sheridan, who comes forward as one of Sophie’s three possible fathers, along with Sam Carmichael (Pierce Brosnan) and Harry Bright (Colin Firth).

While the movie never answers the true identity of Sophie’s dad, using the logic that Alexander Skarsgård is Meryl Streep’s son in Big Little Lies, then Bill Anderson Stellan Skarsgård must be Amanda Seyfried’s dad in Mamma Mia!.

via GIPHY

Fans have also noted this would make Amanda Seyfried and Alexander Skarsgård brother and sister, which is convenient because they share the SAME INITIALS.

The phrase ‘drawing a long bow’ might seem rather apt in this situation, but we shan’t let minor details like geography, timelines and logic, get in the way of a good story.

Does… does this mean that Amanda Seyfried is Alexander Skarsgård’s sister? Is this why they have the same initials? pic.twitter.com/NzFMO3XoTj

— Zoe Samuel (@zoe_samuel) June 11, 2019

Twitter user Molly (@isteintraum) shared this theory with the internet on June 11, and fans have been losing their collective sh*t since.

If Meryl Streep’s son is Alexander Skarsgård I believe we finally have the answer to who the real dad is in Mamma Mia

— molly (@isteintraum) June 11, 2019

pic.twitter.com/0SwKsOn0Gk

— Michael Cox (@MCoxinScotland) June 11, 2019

Bill for the win pic.twitter.com/bPkO5EjtoN

— K.S (@legendarylourd) June 11, 2019

this brings me back to my theory that alexander skarsgård wasn’t cast as Young Bill because he’s too good looking and it would’ve been distracting + difficult to root for sam over him.

— kaki of house stark (@kakicp) June 11, 2019

As I’ve been saying for YEARS, its BILL. They even look exactly alike when he’s younger! End of discussion.

— Jakob Kolness???????? ???? (@JakobKolness) June 11, 2019

HBO UK even tweeted her back, writing “Watch this space for Mary Louise’ rendition of The Winner Takes It All” and we have never wanted a television / movie crossover more.

Me when this finally happens: pic.twitter.com/bbULyZuKkU

— Emmy Potter (@emmylanepotter) June 11, 2019

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