They sat there, fully awake, through the night. Neither of them could sleep while thinking that at any moment the other could be killed.
The Doctor was perhaps the most concerned. After all, River had given all of her regenerations to him. If she died, there was no going back. Not only that, his child would die, as well, without even having had a chance to live.
He had been alone plenty of times, but this would be different. This time, he wouldn't have a choice. His only consolation was telling himself that he had already seen River die. She couldn't die now, or at least if she did, it would create a paradox that could destroy the universe. But without her, what was the use of trying to stop such things anymore? He didn't want to live without her. So he now resolved to sacrifice himself if her life was on the line.
By now, it had to be sometime in the early morning, though the sun had not yet risen. For hours they had been silent. River was leaning against the Doctor, and now he looked down at her. He could see the moonlight reflect off the wetness on her face. Had his hands been free, he would have reached up to dry her tears. Instead, he kissed her cheek softly in an attempt to comfort her.
Still, they said nothing.
Soon, it was daybreak. Now when the Doctor looked down at River, he found that she had fallen asleep. He leaned his head on hers, pressing a kiss into her blonde curls.
The door slammed open, as did River's eyes. A burly guard held her roughly as another bound her feet and mouth. All the time, she was fighting them. The Doctor was on his feet in an instant, kicking the guards and yelling, "You get your hands off of her!" and, "Take me instead. I'm the one you hate!"
The guards paid no attention and even seemed mildly amused, laughing at his feeble attempts at aggression. However, he caught their attention eventually, after landing a kick to where it hurts the most. As the guard he had kicked fell to the floor, the other pushed the Doctor into the cell so hard that he was knocked unconscious.
By the time he awoke, it was the afternoon. After he remembered what had happened, he began yelling River's name as loud as he could, but of course there was no answer. He could barely see through tears of desperation. Collapsing on the floor, all he could do was hope that she was unharmed.
As he lay there, something caught his eye on the floor of his cell. It looked like a shard of glass. Closer inspection told him that's exactly what it was. He felt a sliver of hope rise up inside of him as he maneuvered the glass into his hands. Using it to saw the ties on his hands, he was free in minutes. Triumphantly, he took out his sonic, but then realized once again that the doors were wood.
He remembered how he had seen River pick locks with almost anything. So he took the glass shard, broke it into a thinner piece, and did as he had seen her do countless times. Then he heard a click that could mean one of two things: either the door was unlocked, or the glass was broken, jamming the lock. He hoped with all his hearts it was the first one.
The Doctor grabbed the handle and pushed. To his immense relief, the door slid open. But he didn't have time to cover the evidence of his breakout now; he had to find River before she ended up like the rest of his former cellmates.
He ran as fast as he could through the town, ignoring everyone around him, not noticing that everyone in town was headed for the same place. As he ran, he saw a large crowd in the distance. When he got closer, running became virtually impossible, so instead he pushed his way to the front.
Then he saw her. River was bound just as she had been when the guards had taken her. However, she was still fighting to get free, so a guard had to hold her still. Then the Doctor noticed what was behind her: a cliff.
It all clicked in his mind now. The people in this village would kill all strangers to the planet—especially those coming through their rival town—for fear of being overtaken. He and River had come from the other village after falling from the sky in a blue box. It was no wonder they were superstitious.
Now he was able to catch River's eye. When she saw him, her eyes grew wide, and she motioned with her head for him to leave. He had never before seen her as scared as she was now. Standing his ground, he shook his head in determination.
However, he could see frustration played out on her features, and she began blinking wildly. At first the Doctor was confused, but then he noticed a pattern, a pattern of dots and dashes. She was blinking in Morse code! Once he realized this, he found that she repeated the same five-letter word over and over: T-A-R-D-I-S.
Of course! He slapped his head as he realized what should have been obvious. River gave him a look that said, "What are you waiting for?" and he took off running in the direction from which they had come.
Even though he knew that time didn't exactly matter since he had a time machine, he sprinted the entire way there. Once inside, his fingers practically flew over the controls as he typed in coordinates. Throwing the final lever, he silently begged the TARDIS to take him where he asked for, just this once.
He ran to the door and threw it open to find himself looking up the face of the cliff, breathing a sigh of relief. Then River was falling towards him, so he opened his arms to catch her. She fell into them, knocking him onto the floor as the doors closed behind them.
Quickly, he undid her bonds, and once they were off, her arms were around his head, and she was kissing him forcefully. He didn't blame her. After all, she had almost died, and he had saved her. Therefore, he returned it, wrapping his arms around her waist and pulling her closer.
When they finally broke apart, River spoke first. "I thought you said you wouldn't always be there to catch me when I decided to jump off things."
He smiled softly. "Rule one: the Doctor lies. River Song, I will always be there to catch you every single time you fall, and that is the complete truth."
They were both exhausted from getting little to no sleep, and of course the life-threatening adventure, so eventually River just collapsed on top of him. As tired as he was, the Doctor didn't even bother to take her to their bedroom. He just fell asleep there with her in his arms.