This hapless young woman doesn't get involved in the Transformers' battles on purpose - she just always seems to be in the wrong place at the wrong time. In addition to owning the disguised X-Brawn, she's also had her nerves frayed through Side Burn's constant pursuit of her red sports cars, and frequently goes off on vacations in an attempt to relax, only to have the Transformers wreck those, as well. Kelly was in the tanker truck that was scanned by Scourge to form his alternate mode, and consequently, her human bio-signature was incorporated into Scourge's own. He was later able to use this bio-signature to control Fortress Maximus.

From Wikipedia