It’s heartening to learn neither Ray nor Emma had ever truly given up on escaping, but they’re out of time, so they have to implement whatever plan they have immediately. The key is to distract and misdirect Mama so all of the kids can escape, and the best way to do that is by setting the house on fire.
But Ray knows that won’t be enough, which is why he’s been planning and working his ass off to be the most valuable pieces of meat Mama has ever raised. He’ll set himself on fire so that Mama will stay fixed on trying to save him. And while he brooks no argument from Emma, we never see him actually drop the match into the fire.
Nevertheless, Mama comes out of her office smelling burnt flesh, and finds Emma kneeling before the conflagration in the dining hall, telling her Ray’s in there. She orders an evacuation while she desperately tries to save what she can of her great prize.
She also urges Emma to get out of there, but when she turns around, Emma is already gone. When she tracks her with her watch, she discovers Emma has cut off the ear containing her tracking device. She’s off the grid, and has a huge head start.
When she meets up with the others, Ray is with them, to our surprise. Turns out Emma caught the lit match in her bare hands before it could fall on the oil. She has an alternate plan for Ray that doesn’t require his sacrifice. It’s a plan Norman gave to her, and which she distributed to everyone else bit by bit.
Norman told Emma exactly what Ray would do and how to stop him, including with a pile of meats and human hair that will smell like someone burning. The whole time Emma appeared to have lost all hope and was being comforted by the little ones, she was actually muttering to them the plan that will spring them.
When Emma reaches the wall with the others and prepares to climb, the specter of a smiling Norman pats her on the back, urging her to keep going. But Ray senses somebody is missing…and somebody is. Mama manages to escape the burning house with her radio but nothing else, but she’s determined to retrieve her beloved Emma and Ray. To her surprise, she still has a hostage—with which to lure one or both of them back—in little Phil.
After so much preparation and time-biding, the escape is finally on, and there is no going back, as the home where they used to live has been destroyed. But if I know Emma, she’s not about to leave anyone behind, and that could well lead to her ruin.