The military facility is on high alert, and while Chris manages to escape, he is not the only one to make it out.
When Ben and Maddie attend his mother's fundraising gala, an unexpected guest arrives and offers to end the overfishing that threatens the lives of the mermaids in Bristol Cove.
Those searching for Emma receive help from unexpected allies; Emma struggles to resist her dark urges as she tries to find Merlin before her transformation is complete.
Regina steps up in an unexpected way to protect Emma; a celebration at Camelot turns deadly; Hook tries to bring Emma back to the light.
As the town of Bristol Cove comes to terms with a recent loss following an incident on the ocean, each of its citizens cope in different ways.