"They might think they're real. The perfect disguise. They actually believe their own cover story, right until they're activated."
And Amy is weeping, with a joy she can't name.
As the TARDIS acts up, crazy and frightening, jerking River away from them once again, a fancy dress photo of Rory the Centurion, once upon a time in her hands, and Rory begs Amy to remember him, to love him again -- to marry him -- the trap closes around them all. The TARDIS is under something else's control, here at the site of the explosion, with River inside and the Doctor begging her to break free, or put the TARDIS to sleep, or run out the doors altogether, and the voice of Silence taunting her, and Rory begging her to remember as River fights to get control of the TARDIS again: Somebody else is flying it. Somebody else is in control.
The Romans drop like puppets with cut strings, and rise again. The Doctor can't see them: He's yelling at River to get the TARDIS somewhere safe, before she explodes and makes the Cracks. The Romans open at the wrist, Nestene guns at the ready, as the Pandorica opens. Rory's screaming, up above, begging to stay himself. Begging to be Rory.
"Amy! Listen to me, you have to run. You have to get as far away from here as you can! I'm a thing, I'll kill you! Just go!" He begs, doubled over, as she finally remembers him. Tears running down her face, she puts her arms around him: "Rory Williams from Leadworth. My boyfriend. How could I ever forget you? You are Rory Williams, and you aren't going anywhere ever again."
River is cruel to the TARDIS, looping chains around the doors to jerk them open, and to free them. The Pandorica opens. The Daleks appear, laughing at him. All the old enemies amassed, smiling at the Doctor as the trap closes: The Pandorica is empty, set for the greatest trickster of all time.
Amy begs Rory to stay with her, to stay sane, to be loved and remembered. She asks him about the ring and he produces it. "There it is. You remember. This is you. And you are staying." The miracle is broken, and he shoots her.
River cracks the TARDIS doors, sparks raining down, as Amy dies in Rory's arms. The enemies carry the Doctor to his cell, a chair inside the Pandorica; they gather round as he's locked in, gloating and smiling at each other. They explain, while Amy dies: The Cracks threaten them all. The Cracks come from the Doctor. They don't need his help, they need to save themselves. To save the universe, from the Doctor. He shouts, trying to explain it's the TARDIS that explodes, that it's not necessarily him that creates the Cracks but quite possibly a woman driver -- The Professor in the TARDIS doesn't know -- but they seal him in, and River opens the TARDIS doors: Onto a great brick wall.