Imagine a supercolony of bees (I'm using bees as a metaphor; they're not really bees) which are the constituents of a massive globe-spanning hive mind. The government wishes to exploit this supercolony for its own use: as a weapon to use against enemy forces, which would be a big help.
There's one problem, however. The bees can't be coordinated very easily with external stimuli. They have to be controlled internally, from the central intelligence of the hive. The government begins the search for a person who can be inducted into the hive.
Why would a human be predisposed to joining a hive mind? Preferably, the answer is simple, science-based, and plausible.