The Shards Episodes 3 and 4 premiered on FX and Hulu last night, introducing fans of the Ryan Murphy hit to Ivy Wolk‘s “Really Rhonda,” Dot-Marie Jones‘s porn queen, and a new major theory about the Trawler’s true identity.

**Spoilers for The Shards Episode 3 “Help Me! Rhonda!” and Episode 4 “Robert’s Party,” now streaming on Hulu**

The Shards is narrated by Bret (Igby Rigney), who has been obsessively theorizing that new student Robert Mallory (Homer Gere) is secretly the serial killer known as the Trawler. Bret bases this on the fact that the killings kicked off when Robert came to town and that Robert is a liar. (Bret is specifically upset that Robert refuses to admit that the two boys saw each other at a screening of The Shining the summer before.)

So far, The Shards has given us more clues — from Bret’s perspective — that Robert shouldn’t be trusted. He makes lewd comments about their mutual friend/crush Susan (Kaia Gerber), is seen arguing with Matt Kellner (Owen Painter) before the boy’s disappearance, and is seen skulking off to a creepy house on Cielo Drive. In a dramatic sequence, Bret imagines that Really Rhonda is being kept prisoner there, but a clever trick of editing reveals that the teen isn’t on the cusp of cracking the case after all. She’s being held elsewhere.

The Shards Episode 4 “Robert’s Party” takes place at, you guessed it, a party Susan throws to welcome Robert to the Buckley social scene. We’re told that Robert doesn’t drink because it would interfere with the medication he takes. We also learn that Robert’s mother died in a mysterious accident and that he was institutionalized for a time afterwards. Oh, and that there were rumors that Robert killed his own mother.

Naturally, Bret seizes upon this grim bit of gossip as not only being gospel truth, but also proof Robert’s a serial killer. So Bret makes a snide comment to Robert that he knows he killed his mother. Robert’s reaction to this will either feel like confirmation of Bret’s wild theories or proof that Robert’s just a traumatized teenager trying to escape the darkness of his past.

Robert downs a handle of vodka and then begins to erratically dance in front of everyone to the Go-Go’s. When Thom (Graham Campbell) tries to calm him down, Robert begins fighting back. Soon Thom is trying to subdue Robert in a wrestling pose, but Robert starts kissing Thom. Robert then takes his clothes off, walks barefoot over the shattered vodka bottle, and cannonballs into the pool. Thom and Susan have to jump in after him to save him. (Oh, and Susan has to give him mouth-to-mouth.)

“It was really fun to shoot that,” Homer Gere told DECIDER. “Those were all night shoots filming outside and doing the dancing stuff and everything. It was really fun and freeing, I think, as an actor for me to be like doing these insane things in front of a hundred background actors and all the crew and everything.”

“I feel like I got outside of myself in a really fun way. It was really fun.”

But what does it all mean? And what does it mean that while Robert was cutting a rug on the dance floor, cult leader Bruce (Gus Halper) was threatening the lives of Debbie (Hayes Warner) and Ryan (Daniel Dale)? Here’s what you need to know about the end of The Shards Episode 4…

The Shards Episode 4 Ending Explained: Why Does Robert Freak Out at the Party? Is Robert Mallory the Trawler?

There are two obvious ways to interpret Robert’s actions at the end of this week’s The Shards.

One, Bret accurately discovered that Robert is the Trawler and he freaked out, immediately owning up to his erratic psyche. Or Bret triggered Robert with the comment about killing his mother, prompting the other boy to escape into alcohol, which in turn screwed with his medication.

When DECIDER told the stars of The Shards that we felt “awful” for Robert, Homer Gere immediately thanked us and Igby Rigney fired back.

“Don’t side with this guy!” Rigney said.

“I appreciate it,” Gere said. He then added, sarcastically: “Igby’s a terrible, terrible man,”

“No, no, no! He comes into our school lying about where he was last year,” Rigney said. “I just want to say that’s not a good look.” 

“Robert is a man of high repute,” Gere said.

Basically, like a lot in The Shards, it’s up to your point of view. What’s not up for debate, though, is that Thom has a secret…

Who is Hiding in the Closet in The Shards Episode 4? Is Thom in the Cult, Riders of Afterlife?

We learned in The Shards Episode 2 that a cult known as the Riders of the Afterlife is also preying upon the youth of Los Angeles. Their leader is Bruce, a former teacher.

Bruce is the man hiding in Susan’s bedroom closet who threatens Debbie and Ryan at knifepoint. This means Bruce could very well be the Trawler, or simply responsible for some of his crimes. (Remember the cult’s symbol was in Matt Kellner’s bedroom.)

What’s even more shocking? Bruce only stands down because Thom talks him down and Thom very obviously knows Bruce. How does Thom know Bruce? Is Thom in the cult? We’ll have to wait until another episode of The Shards to find out…

The Shards Episode 5 “Murder on the Dancefloor” comes out on Wednesday, August 19 at 9 PM ET on FX and Hulu.