A/N: I'm going out of town tomorrow until Sunday, so this might be the last chapter for a while. Sorry! I will try and get another one done before I go. And then, the Wednesday after next, school starts. :P

The Doctor did not bother to look up as the TARDIS door opened.

It was a day later, and he was still working on the "machine that goes ding". He was bent over the pile of circuits and metal, picking at them with some strange instruments.

"Hello, sweetie."

"Hello, River." He said absentmindedly.

"Have you still not assembled that thing yet?"

"No." He moved a wire, looking at the blue and red circuits that poked forth from the rubber covering, trying to figure out where they connected. "My past self likes to pretend he knows everything about building machines that go ding, but really, he doesn't know a thing about assembling space-time anomaly detectors. He was never good at building."

River stepped forward, eyeing the pile of disarrayed metals. "Is 'the machine that goes ding' the best name you could come up with?"

He looked up at her, blinking his green eyes at her through the goggles that magnified said facial feature ten times their normal size. "Yes, unless you want me to call it the 'Alomaly-inator'…" He went back to his work. "Never mind. That's a rubbish name."

She chuckled at his odd appearance with the goggles and disheveled hair. "I never got to say goodbye to your past selves."

"You see them again. My memories say so."

"You always acted as if you were jealous of them. Especially your tenth self."

He frowned at his wife. "I was not jealous!"

She raised a skeptical eyebrow at him. "Really?"

He stood up, puffing out his chest. "Okay, maybe I was a little jealous. I don't like my past selves impeding on my wife, okay?"

She walked forward, laying a hand on his chest, feeling his double heartbeat vibrate beneath her fingertips. To her, there was not a more calming sensation. She looked up into his eyes, smiling. "Don't worry about it. You'll always be my Doctor."

He kissed her forehead gently. "Glad to hear it." He turned back to his machine. "Want to help me try and figure this out?"

"Sure." She looked down at the pile. "Though I'll tell you now, I'm an archeologist, not a technician of any sort."

"Well you can hand me tools. Simple enough?"

"Sure…"

"Wrench."

"This thing?" River picked up a bizarre looking item that looked nothing like a wrench.

"Yes." He took it from her and levered away at some bolt, causing another electrical short and more sparks to fly.

Not much had been accomplished in the last hour. As best River could tell, he had done some things with the circuits and placed two pieces of metal and a light bulb together. That was all she could tell amidst the many parts that lay before them.

He handed the wrench thing back to her. "Screwdriver."

She looked back at the row of strange tools that lay on the bench behind her. "Your sonic?"

"Yes." He gave a look as if she was being thick. "Believe it or not, my sonic screwdriver also functions as a screwdriver!"

With a sigh, she handed him the instrument.

His appearance had become even more raggedy over the past hour. His shirt sleeves were rolled up, but were still smeared with ash and oil, as was the rest of his body. His shirt had multiple burn holes from the sparks that frequently shot from the wires. His hair was a catastrophe, covered in ash and oil and matted together in a big brown sticky mess that clung to his forehead with the sweat on his brow that came from the heat of the machinery.

River remained immaculate, as always. Every time he got ready to have a go at the mess with a tool, she stepped a good bit away, preferring not to get burned or splattered.

They both jumped slightly as the TARDIS door opened with a loud bang, and the Master walked in.

"Oh!" The Doctor yelled in frustration, holding a wire with his tweezers and shaking his screwdriver. "I was just about to connect a wire to this screw! It's a very painstaking process that must be perfect!" He glared at the Master. "Nice timing!"

He grinned at him. "As always." He threw his jacket over the railing. "Well Doctor, apparently you're going to have to be my best man, as much as I detest that."

The Time Lord in question turned around, peeling the goggles of his face to stare at the Master clearly. "What?"

"Yeah. Clara said I had to tell you that you were going to do that."

He grinned the blond. "I would be more than happy to do that for you."

The Master turned to face them. "She says a rehearsal starts soon and that you two have to come."

"I'll get right on it!" River ran down the stairs and out of the TARDIS.

"Tell her I'm busy." The Doctor said, turning back to the pile of parts that he was focusing on. "I have to build this thing to catch the Zygons. I look like a mess anyway."

"Fine, but if she forces you to come, it's not my fault."

Apparently, Clara had consented with him because after the Master left, he did not see sight or sound of anyone else.

Now, he stood alone in his TARDIS, fiddling around with the machine. It's not that he wouldn't mind being at the rehearsal, but he thought the Zygons invading earth were a larger priority at the moment. Why did you need to practice a wedding anyway? He never practiced. Apparently, Clara felt safe with planning a wedding with aliens anywhere around her when he was on the job.

He crouched low, painstakingly moving a wire towards a screw ever so slowly. This was the moment! Contact was made, and it sparked again, but the contraption started up, the gears whirring and the lights flickering, small screen wired to the thing flashing on. It was still just a big pile of wires and metal and lights mostly, as he had not put together the outer shell of the machine yet, or worked out all the kinks.

"Yes!" He spun in a joyous circle, clapping his hands, excited that he had finally made some progress. He paused, looking down at the thing. "What's this?"

He leaned close to the screen, reading what the red letters said.

ZYGON MOLECULES DETECTED

"What…?" He looked around the TARDIS, looking for something out of place, but nothing appeared to be different, aside from the Master's coat that he had left hanging on the rail from when he had been there earlier.

Just out of curiosity, he walked over to the coat and grabbed it up, holding it out towards the machine.

Ding.

He blinked. The machine had gone ding! He walked toward the machine, holding the jacket in his outstretched hand. As he drew near, the dings grew more frequent, signaling alert.

He looked at the screen again and it read:

ZYGON ENCOUNTER IMMINENT

He looked from the machine to the coat, a feeling of dread building in the pit of his stomach. At that moment, the machine died, powering down as it still wasn't finished. He stared at the coat for a minute, putting the pieces together in his head. Then, without bothering to take off the goggles that still dangled around his neck, he tore out the door.