Why Does Toby Punch Caleb?

In many ways, Season 6B of Pretty Little Liars has set the reset button on the series. Big A, a.k.a. Charlotte DiLaurentis, was mysteriously murdered in the premiere, meaning that she's no longer around to dish out the torture that she was secretly orchestrating for over three seasons. Of course, that's not the only thing that has changed five years after the Big A reveal — as Caleb might say, "personal dynamics have shifted." Not only are Hanna and Caleb over (and have been for a few years now), but Spencer and Caleb are officially an item. Move on over, Spoby and Haleb: Spaleb is now walking the streets of Rosewood, and it's even more of a shock than Uber A taking over for Charlotte. Now, a new promo for PLL episode "Burn This" hints that Spencer's former boyfriend Toby may be fighting with Spencer's new love interest, Caleb — despite the dudes' former bromance. Toby punches Caleb in "Burn This," and why might be an even bigger question mark than Uber A's identity.

Right now, we don't have any clue why Toby would shed his often calm demeanor to punch his former pal right in the face, but that doesn't mean we can't theorize. What could have caused this bromance to fracture to the point of blows? Here are a few ideas — but first, the punch heard around the world:

1. Toby Finds Out Caleb Leaked The Info About Yvonne's Past

In the episode "We've All Got Baggage," Caleb takes the blame for leaking information about Toby's girlfriend Yvonne's high school abortion. It's not actually Caleb who provides that info, of course — Caleb confesses so that Spencer doesn't get caught up in the new villain's web — but it's not like Toby would know that. Toby may have taken a swing at Caleb in order to defend Yvonne, who was likely devastated by such a personal situation coming out during the election. It certainly is in Toby's nature to defend his girlfriend in times of trouble.

2. He's Secretly A Lot More Bitter About Spencer And Caleb Than He's Letting On

Toby is dating (and proposing to) Yvonne, but that doesn't mean he hasn't stopped loving Spencer. After all, it's not like their relationship blew up in any real way: they simply grew apart due to distance. He's also dating someone eerily similar to Spenc — so similar, in fact, that their parents are competing for the same senatorial slot. Could he finally see Spencer and Caleb together and just snap?! It would be awfully dramatic, but hey, it's PLL.

3. Toby Finds Out That Caleb Has Been Lying About His Mother's Death

We haven't heard much about Toby's mother's story this season, so what if the girls never told Toby that Bethany killed his mom? If Toby didn't hear the truth, and then Caleb revealed it a little too late, it could definitely destroy Toby and make him lash out.

4. Toby Finds Out That Caleb And Spencer Kissed Before Toby And Spencer Broke Up

Spencer said that she and Caleb reunited a few years back when Spencer was studying abroad, but what if her and Toby hadn't broken up by that point? Though it wasn't clear whether Spencer and Caleb actually

during that Spain trip, there's a real possibility that they at least kissed. If Toby found out about that, he would have every reason to be hurt, despite his current romantic situation.

Personally, I hate it when these two bros fight... can't we go back to the days of the ex-boyfriend brigade and microbrews? This new reality is just too sad.

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