Prior to the Last Great Time War
"Sweetheart, I've already made plans to stop over in Siberion. I have a few things to take care of. It won't take very long," she assured him, kissing him lightly on the cheek.
"Are you sure this a good idea?," he replied, looking her over as she darted around the TARDIS, checking the readings and flipping switches here and there.
"I promise, it'll only be a few days. They asked for my help, so I'm helping."
"I just feel like now isn't the best time. Something's wrong; horribly wrong."
"Doctor," she said soothingly, "You know me better than anyone else. I'll be alright."
He wrapped his arms around her, his fingers stroking her wavy black hair. Her eyes peered deep into his as he pressed his lips to hers.
"I know darling; I just don't know if it's a good idea. I worry is all."
"I'll be fine. It's only three days."
He smiled at her faintly before she walked away, and he stood there watching her TARDIS vanish.
Present Day
"Oh my god...," he said out loud, unaware that Martha could hear him.
"What is it Doctor?"
"What? Oh, oh it's nothing."
"I know that tone. It's not nothing. So what is it?"
He removed his glasses, polishing them on his sleeve before he looked up from the monitor and stared at her.
"We have journey to make. A very important journey," his eyes lit up to disguise the fear and confusion running rampant in his head.
"Where to?," she asked, excited.
"I'll explain when we get there," he replied, "But for now, just know that it's of utmost importance."
With that, they were off.