Pokémon Adventures: Black and White Vol 3

From the VIZ Media edition

A precious fossil is stolen from the Nacrene Museum! Can Black track it down by... following its tracks? Then, mysterious Team Plasma is one step closer to bringing back a Legendary Pokémon. What are they up to? Probably no good! Plus, will Gigi and Tep's relationship survive a major change?!

Source: Anime News Network Encyclopedia