Like her subjects, Emmaline distrusts humans for the attack on her Kingdom as shown when she gets negative with Sofia after finding out that she's a human. However, she does believe in giving everyone a chance to do the right thing.
Role in the Series
She first appears after Sofia follows Cora and Oona back to the coral castle. Oona and Emmaline both have a dispute over the Floating Palace's presence in the cove and they discover Sofia followed her daughters home. She tells her daughters and Sofia about the attack on her Kingdom and that that's why her people avoid going up to the surface. Sofia tries to assure her that the humans on the ship mean no harm but Emmaline and her chief advisor, Plank, don't take her seriously both because they think she's a mermaid and because they know she's a child. When Plank proposes that Emmaline uses her trident to conjure a storm to blow the ship out of the cove, Emmaline is against the plan because it might sink the ship. Sofia offers to go up and get the humans to move the ship on their own. When Plank asks her how she would do that, she reveals she's really a human and that the ship belongs to her family. Emmaline and her subjects are all shocked by this revelation except Oona, who knew all along. When Sofia give her her word that she'll get the ship to leave immediately, Emmaline orders her to do so and to never come back.
When Sofia comes back and tells her that Oona has been kidnapped and when Plank accuses her family of doing so, Emmaline warns Sofia that she has until sundown to return her daughter or she'll use her trident to sink the Floating Palace. When time is up and Oona still doesn't come back, she uses her trident to conjure a storm.
Sven, who saw the sea monster that Sofia said abducted Oona with his own eyes, stops her before it gets too fierce and leads her to where Oona is being held where she is reunited with Oona who tells her that Sofia was telling the truth all along and that Sofia saved her. After apologizing to Sofia and stopping the storm, she becomes friends with Sofia's family.
She makes a non-speaking appearance in the episode, "Cool Hand Fluke" where she watched, along with Cora, as Oona's band performed a song, thanking the Royal Family, for throwing a party for them.