Here is your one stop shop for everything you can expect to see in season 4 of Once Upon a Time.

In just three days, Once Upon a Time will return to television. Since the moment Elsa’s icy hands were revealed in the season 3 finale, a firestorm of casting news, story lines, and relationship speculation has hit the internet. If you missed anything from May 11 at 9 p.m. through September 24, our guide to season 4 has you covered!

Looking for ‘Frozen’

The news of the Frozen addition to season 4 pitted fans either for it or against it at the start of the summer hiatus. Regardless, Adam Horowitz and Edward Kitsis charged forward with their vision and the casting began!

(Even Sven was included!)

In early July, Anna and Kristoff were cast. Filling the role of Anna is Elizabeth Lail and Kristof is played by Scott Michael Foster. Viewers will pick up with them on Once Upon a Time following the events of Frozen in Arendelle right before Anna and Kristof are set to wed. Just two short days later, Georgina Haig, took the role of Elsa!

Familiar faces, rock trolls, and… a new villain?

Over the course of the summer MUCH more casting news came in from every corner, including Wonderland. Michael Socha, from the Once Upon a Time spinoff, will reprise his role as the Knave of Hearts and a former member of Robin Hood’s Merry Men. But do not expect him to be welcome in Storybrooke right off the bat. In the earlier episodes of the season, viewers will find out what events transpired after his happy ending with the Red Queen and what brings him to town.

Elizabeth Mitchell responded to a casting call and her character’s identity was swept under the rug for a large portion of the summer. That is, of course, until Horowitz and Kitsis hinted at enough details so all evidence pointed to her portraying the Snow Queen from the original Hans Christian Anderson story. Following her casting was another villainous character, this time from the Disney adaptation. Prince Hans’ shoes will be filled by Tyler Jacob Moore (Shameless).

CGI, oh CGI, where are you? No combination of pixels will bring Olaf to your screen this fall, but they will be able to muster up some rock trolls. Pabbie, the father figure in Kristof’s life, and the wise leader of the trolls, will make an appearance in the first episode of the season voiced by John Rhys-Davies.

(Sorry, Olaf… Your story was best kept as is.)

Next page: What’s Happening in Storybrooke?

Let’s get back to Storybrooke:

Then came Comic-Con. While filming was still in the early stages at this point, there were a few tidbits about relationships, clothing changes, and the integration of Anna and Elsa into the world that we further explored as the summer wore on.

Colin O’ Donoghue is the first person to be grateful for the wardrobe change that suggests dropping his heavy jacket in favor of some more modern attire. O’Donoghue describes it as “a ’70s rockstar…an element of who he is, even though he’s trying to fit into this world. It’s his idea of what it would be like.”

As for Hook and Emma, in an interview, Kitsis mentions Hook’s future courting Miss Swan on the show saying, “If you notice, they haven’t had a proper date. Their dates have been running from time travels and portals and monsters, so they’re going to have a proper date.”

As for Rumpelstiltskin and Belle, they will have their honeymoon to look forward to in the premiere. But what about that whole dagger swap thing? At least for the better part of the first half of the season, Belle will remain in the dark, but Carlyle remarks, “It’s going to be bad at the end of episodes 9 and 10 for Rumple.” In the second preview of the show, a very special dance is also on the way for the newlyweds!

Belle’s mother is also set to make an appearance later in the season as Belle’s past becomes a major part of her future life. The role of Colette will be played by Frances O’ Connor and she will appear in flashbacks only.

The Charmings and their newborn Prince Neal will have a few shakeups this season as well! In light of Anna and Elsa’s arrival in Storybrooke, David’s past will reveal a connection to the sisters and Arendelle that may very well be the most important friendship that, “has really changes the entire course of his life and sets him on the path of becoming the hero that he is.” Meanwhile, at home, Mary Margaret will step back into the workforce in a major leadership capacity. But is she about to step over Regina’s role in the town?

Speaking of Regina, she has her own demons to battle as her heart breaks at the start of the season with the return of Marion. Regina’s character has significantly grown from her roots as the woman who would rip your heart out without batting an eye. But will that be enough to help her keep control as her happiness vanishes right in front of her? Perhaps her call to Sidney Glass casts just enough distance between herself and the act she wishes was committed.

Related: Watch a sneak peek of Regina reuniting with her Mirror!

Regina has another relationship to work on with Emma. After all, what do you do when the biological mother of your adopted son brings back a woman from the past who you previously executed and ruins your one shot at happiness? Um… While we may not be sure what Regina has in mind, Morrison assures us of Emma’s plan, saying, “She’s going to spend time fighting to prove her friendship and fighting to keep Regina in a good place.”

Henry! You around? After a very prominent storyline in the first half of the season and memory loss for the second, Henry will have a large overarching storyline for season 4 that does not involve the crew of Operation Cobra. Instead, Henry and Regina will team up and work together in a whole new way!

As for all the family history of last season, Jared Gilmore is excited to see Henry working through his new relationship with Mr. Gold. Gilmore adds, “Henry is going to learn a lot this season, which is going to be great for him because he’s going to learn what he’s meant for.”

PHEW! Got all that? And that is just for the first half of season 4! Remember that Maleficent (Kristin Bauer van Straten) is set to return for the spring portion of the season. But let’s get through episodes 1-11, shall we?

Related: Watch the first 7 minutes of the premiere here!

Be sure to tune into the ABC special that will cover Once Upon a Time season 3 at 7:00 p.m. and get you ready for the premiere airing at 8:00 p.m.

Once Upon a Time returns Sunday, September 28 at 8:00 p.m. ET on ABC.