Characters: Jack Harkness and Rose Tyler; mention of Nine, Ten and Martha Jones; Toshiko Sato later 'cause I love her, damn it!
Summary: Sometimes a bet takes some doing.
Notes: Written for the ficathon over on the LJ community notsobigheaded. We happily live in denial of the revelations at the end of LotTL.

Jack grinned as the blonde nearly fell off the bed, laughing at the fairly raunchy joke he'd just finished telling her. It was only when the Doctor was busy working on the TARDIS that he and Rose could sneak off and just hang out like this, drinking and telling jokes that would more likely than not earn them disapproving looks than a laugh or two from the Time Lord. Especially a joke involving humans, aliens, a bar, and hypervodkas.

"Oh, that's wonderful!" Rose crowed, setting her beer aside as she climbed back up onto the bed. "I'm not sure what a Trellaxian is, but that's hilarious!"

Jack grinned again. "Heard that one from an old friend, of a sort. Nice guy, for having no limbs."

Rose's eyes widened and she waved one hand as if trying to pull facts from the air. "That reminds me! The first place the Doctor took me - after blowing up my job, that is - was to the end of the world. I met the last human - bitchy trampoline! - and a head in a jar!"

The ex-Time Agent blinked at her. "You're kidding."

Rose shook her head emphatically. "No, he was a giant head in a jar. Called him the Face of Boe."

At that, Jack started laughing again. "That is a great coincidence. Old Boe's the one who told me that joke."

"Now you're kidding."

Jack grinned. "I kid you not, fair Rose. I was born in the Boeshane Peninsula, and was the first person from the area recruited to the Time Agency. The media had a field day with it, since some people just called it 'Boe' for short; what better way to promote the Agency than to have Boe himself meet and greet the new recruits?"

Rose took a drink from her bottle and snickered. "So, you're the Face of Boeshane," she remarked... then burst into renewed laughter. Jack stared at her for a moment, wondering if she was going to be all right.

"Um, Rose?" he asked, making a mental note that five microbrews was probably beyond her limit.

She got herself under control and gave him a challenging look. "Bet you can't make the Doctor think you're him."

That... made no sense. "Come again?"

"Bet you five quid you can't make the Doctor believe you are, were, or ever will be the Face of Boe," she repeated, grinning wickedly.

Jack blinked slowly. "You mean aside from the fact that he's a completely different species?"

"Yep."

"And the fact that he's at least a thousand years older than I'll ever be?"

"Yep."

"And that fact that I'm good-looking - even if I do say so myself - and Boe's a head? In a jar?"

"Yep."

Jack smirked. "Make it ten and you're on."

-----

Over one hundred years and several deaths-and-rebirths later, Jack found himself watching the CCTV shots from when the Doctor had dropped him off after the Year That Never Was. Seeing the looks on the Doctor and Martha's faces after he'd walked away was priceless even a month later, and he couldn't help but laugh at the Time Lord's utterly gob-smacked expression.

It was this laugh that lead to Toshiko peeking into his office and giving him an odd look. "Jack, are you okay?"

Jack muffled his laughter and nodded. "Yeah, I'm great," he remarked. "A little annoyed, but in a good mood overall."

Tosh smiled and leaned over his desk to see what he was watching, lips curling into a smile as she noted that her boss seemed to be smitten with the man on the screen. "Why annoyed?" she had to ask.

Jack grinned. "Because I'm never going to see the ten quid from a bet I made a long time ago."