Elsa and Anna are finally reuniting in the brand new episode of "Once Upon a Time" season 4  titled "Family Business."

Elsa (Georgina Haig) has gone all out to find her younger sister, and their reunion finally happens in Arendelle of the past.  But when Elsa inquires if Anna (Elizabeth Lail) has found out anything significant about their parents' trip to the Enchanted Forest, Anna has no definitive answer to give.

She says, "I'm still waiting for answers from a few people I met, it could take a long while."

However, Anna notices something different about Elsa's demeanor. The older sister is now calmer and able to manage her powers.  It turns out that Elsa is getting help in controlling her powers from the Snow Queen (Elizabeth Mitchell), which is a bit surprising since she was not a friend to begin with.

The Snow Queen's real motives will also be in question in episode 6, as Belle (Emilie de Ravin) will go to all lengths just to force Mr. Gold (Robert Carlyle) to show her where the icy queen is.  Viewers will also find out that the Snow Queen happens to be Emma Swan's (Jennifer Morrison) former foster mother when she was young.

The entire synopsis of the upcoming "Once Upon A Time" episode reads:

"The race is on to track down the elusive Snow Queen, who was once a foster mother to a young Emma – whose memories of this event have been erased – in order to discover what her ultimate end game is for Elsa and the residents of Storybrooke. Unaware that she does not possess the real blade that controls The Dark One, Belle attempts to use it to get her reluctant husband to show her where the Snow Queen is hiding. Meanwhile, back in the past, Belle travels to Arendelle and, with Anna's help, seeks out Grand Pabbie to help her regain her lost memories."

Aside from Anna and Elsa, other Disney's "Frozen" characters will also be featured in the new episode, such as Anna's true love Kristoff (Scott Michael Foster) and the shopkeeper named Oaken (Darcey Johnson).

"Once Upon a Time" season 4 airs every Sunday on ABC.