Have theories on the mystery of 'Big Little Lies'?

Five episodes down, two to go, and "Big Little Lies" still hasn't revealed many details about its huge central mysteries: Who's dead and who's responsible? There's a constellation of lesser head-scratchers that seem so tied up in that huge one. Who's Ziggy's rapist father? Who's bullying Amabella? And most importantly, is there anything scarier than puppet nightmares?

The tension just keeps building, making it increasingly difficult not to throw in the towel and head to Wikipedia where a synopsis of the novel by Liane Moriarty will reveal all. But for those who haven't read the book - and have maintained their will power - let's talk about where the clues are leading, starting with Ziggy's dad.

Assuming Jane (Shailene Woodley) is telling the truth, Ziggy's father was a charismatic guy who said his name was Saxon Banks, and he picked her up at a bar, took her to his hotel room, raped her and disappeared. But Saxon Banks doesn't really exist. Could he be Saxon Baker, the smartly dressed San Luis Obispo interior designer, who Jane went to confront in last night's episode? It doesn't look like it since she stormed out of his office after getting just close enough to sniff him.

The elusive Saxon could obviously be some random person, but what if he's a character we already know?

In that case, the most obvious choice would be abusive husband Perry Wright (Alexander Skarsgard). From what little we've seen from Jane's flashbacks, Perry could be a match physically, plus he's always traveling for work so it isn't far-fetched to imagine him ending up in Jane's previous home town. Jane also mentions he's keen on erotic asphyxiation, and how often have we seen Perry wrap his hands around the neck of his wife, Celeste (Nicole Kidman)? But is that too obvious? Maybe he's a red herring. In which case, Saxon could be ...

Ed (Adam Scott). It's kind of hard to believe, since Ed is such a beta male in most scenarios. Madeline (Reese Witherspoon) obviously wears the pants in their relationship, and yet Ed has done some strange, borderline creepy things. He made that weird comment to Bonnie (Zoe Kravitz) about enjoying the sight of women sweating, followed shortly after by a skeevy look at the rear view of a passing blonde in yoga pants. The camera also caught him staring at his teen step-daughter. Still, if he had a propensity for violence, you'd think he would have clocked Madeline's ex Nathan (James Tupper) by now.

Speaking of Nathan, could he be Saxon Banks? So far there's not any evidence to support that.

That just leaves Gordon Klein (Jeffrey Nordling), who can't be faulted for much beyond his creepy transition lenses and the way he's victim-blaming his daughter Amabella (Ivy George) after she was choked and bitten by a mystery bully.

So who's the bully?

If Amabella's first instincts were right, then it's Jane's son Ziggy (Iain Armitage). The problem is, he seems like such a sweet kid, plus a child psychologist thought he was innocent. In fact, the therapist thought perhaps Ziggy was being bullied, too. Of course we know he does strange things in his sleep so could he have sleep-walk-attacked Amabella? That seems more unlikely than if it had simply been ...

The twins. They are, after all, the son of Perry. (Then again, who knows? Maybe Ziggy is, too.) It's possible they've seen the way their father abuses their mom and think it's normal to choke and bite their buddies. They're clearly into rough-and-tumble play, and we've seen them ganging up on their mom (in an admittedly playful way). Plus Amabella said she didn't know who had bitten her and if she can't tell the difference between the identical boys, maybe she wasn't lying.

There's also Chloe, of course, Madeline's daughter and the queen bee of the classroom. But she seems more like an instigator than a kid who would do the dirty work of physical bullying.

If the most obvious answer is the right one, then the likely scenario is that Perry raped Jane and his twins are bullying Amabella - and maybe Ziggy, too.

So if that's the case, who's dead and who's the killer?

Even by narrowing down the other mysteries, this one is still amazingly open-ended. Could Jane have met Perry at the fundraiser, figured out he was her rapist after hearing his voice and killed him? Or could Madeline, who so loves to get involved in other people's drama, have done it on her new best friend's behalf? Or maybe Celeste finally realized the only way to truly get away from her abusive husband is to kill him. Of course Perry is as likely as anyone to be the killer, given his history. And at least a couple of people have motive to kill Madeline that have nothing to do with the identity of Ziggy's father.

All of which is to say that the central mystery is still a huge question mark. But that's OK. It's half the fun of the show.