Numb3rs Fanfic Finders

I'm looking for a good plot-based, multi-chaptered fic. I'm good with strong subplots on interpersonal issues (romantic or otherwise), but I want an actual case for them to solve, too. I've seen some of those with Megan, but not any with Liz or Nikki that I can find (Liz and Megan both would be lovely, too), and I'm just interested in one set later. I like Liz and Nikki. And I like the idea of David's growing supervisory role, Charlie/Amita well-established, and Charlie not incessantly referred to as a skinny kid. It would be a plus if Larry and/or Amita to play in, since I really do adore my geeks, but not necessary. Canonical couples for time period, please.