This was inspired by a thing on tumblr. Read and review. Yours truly, Sherlocked Gallifreyan.
It had been many years since Amy had last seen the Doctor. "Well, Rory," she said. "Maybe you were right. Maybe he's forgotten about us. It's been thirty years since he last visited." She looked up as lightning flashed across the sky. "I'll visit again soon," she promised, kissing the rose in her hand and laying it in front of the grave marker. Amy walked back to her car as the rain began to fall. She paused with her hand on the car door and looked back at the cemetery. Thunder crashed as she slid into the driver seat and started the car. Before she drove off, she touched the TARDIS charm on her keychain. She had done that for the last thirty years.
She pulled into her driveway and shut off the car. As she was getting out, she noticed that the front door was slightly ajar. I could have sworn I shut and locked the door, she thought. Grabbing the pepper spray from her purse, Amy cautiously advanced into her house.
And stopped abruptly. The TARDIS, large as life, was in the middle of her living room. But the man coming out of her kitchen, eating a leftover hamburger, was not the Doctor she remembered. He was shorter than the Doctor she remembered. His hair was considerably darker, and there was stubble on his jaw. He wore a tan trench coat over a dark suit. There were bloodstains on his white shirt, and his dark blue tie was either on backward or twisted so it appeared backward.
He looked at her in shock, blue eyes wide and confused. "Who are you?" Amy demanded, holding the pepper spray out like a gun.
"My name is Castiel," he said, holding his hands (and the hamburger) up. "Are you Amy?"
"How do you know my name?" she asked, shifting her grip on the pepper spray.
"The Doctor told me to find you," the man named Castiel said, edging away from her.
"Where is he?" Amy asked, looking around for the Doctor.
"He's dead," Castiel said.
"Where is he?" Amy repeated.
"He died saving a six-year-old you from something called a multi-form," Castiel said. At least, I think that's what he called it.
"What about everything that I remember?" she asked, lowering the pepper spray.
"It all happened," Castiel said. "He dies after all of those adventures."
Slowly, Amy walked around the sofa and dropped into it. "He's dead? I guess that would explain why he never showed up again," she mused. "Rory was right all those years." She looked up at Castiel. "What happened?" she asked.
Castiel sat next to her and gently placed his hands on either side of her face. A foreign presence touched her mind, and she saw memories flood before her mind's eyes.
The Doctor was saying something, but she couldn't hear any of the words. A strange howling made sure of that. The Doctor pointed, and she saw the multiform. But everything was different. They appeared to be in the middle of a parking lot. She saw her six-year-old self pressed against an abandoned building, her face tear-stained. The Doctor spoke again, motioning toward the six-year-old Amy. There was a brief flash of white, and she was in a room. "Stay here," a voice said. She recognized it as Castiel's voice. Six-year-old Amy nodded.
There was another flash of white, and she was back in the parking lot. A strange knife appeared in her peripheral vision, then suddenly dropped away. There was yet another flash of white. Now, she was kneeling over the Doctor, who was lying propped up against the building, bleeding heavily from a gash in his abdomen. The Doctor tried to speak, but he started coughing up blood. She watched in horror as the light faded from his eyes. A hand entered her field of vision and closed the Doctor's eyes.
Amy didn't realize she was crying until the strange presence withdrew from her mind. "I'm sorry, Amy," Castiel said, not making eye contact with her. "By the time I got back, it was too late to save him. I'm sorry." Castiel blamed himself for the Doctor's death, the same way he blamed himself for the deaths of Sam and Dean.
"It's not your fault," Amy said hollowly. "I guess I already knew he was dead. It'd been thirty years since Rory and I last saw him. Rory… my husband… died twenty-two years ago."
"I'm sorry," Castiel said, not knowing what else to say.
Amy wiped away her tears. "The TARDIS… Is she okay?"
"She's… coping," Castiel said. "His death was very hard on her. Would you like to see her?"
"I'd like that," Amy said, pulling the key from under her blouse. She unlocked the doors and pushed them open. A warm hum ran through the TARDIS, her way of saying hello. Amy crossed the threshold, looking around. The ambiance was dimmer, and the TARDIS seemed depressed.
"Hello, old friend," Amy said softly, gently stroking the center console. "It's been a very long time…"
I think I'm just gonna end it here, but I'm not sure yet.