Alexander Skarsgard, please tell me that is not your penis

Alexander Skarsgard has bared all in Big Little Lies. Photo / Supplied

Note: This article contains minor spoilers for Big Little Lies.

A racy scene in the States' latest episode of Big Little Lies left fans all aflutter as they tried to decipher whether they'd just seen Alexander Skarsgard's real penis.

The dramatic moment came as the actor - who plays Perry Wright - fought with onscreen wife Nicole Kidman (Celeste) in a shoe closet with his fly undone and his manhood exposed, the Daily Mail reports.

It wasn't long before viewers took to Twitter to discuss what they'd just witnessed on the HBO show, with many assuming it was a prosthetic appendage.

But some fans excitedly tweeted that they'd just seen the star go full frontal.

"I was not expecting to see ALL of Alexander Skarsgard but woah" another shocked viewer posted.

During the scene, Perry gets angry at Celeste for turning down his advances as he tries to get frisky while the couple are preparing to go and see a play. Celeste hits back at her husband by whacking him in the groin with a tennis racquet.

If it is indeed real, it's not the first time the Swedish star has let it all hang out on TV, as the 40-year-old actor once bared all on the season six finale of vampire drama True Blood.

The Hollywood hunk has previously discussed how comfortable he is with nudity.

"I was 14 the first time I saw my dad wearing pants," he said in 2013 about his father, actor Stellan Skarsgard. "He was always naked. Always naked. When he wasn't at the theatre he would be at home cooking or just chilling with no clothes on.

"Parents in the States freak out if their kids see a nipple or a butt cheek, but at the same time they're OK with their kids watching people bash each other's heads in with baseball bats," he said in an interview with OUT magazine.

We know what we're thinking though:

Big Little Lies airs Sunday at 8.30pm on SoHo.