I cannot for the life of me track down the name of this flower. Google image search wasn't much help either.
Possibly Dahlia cv. Seduction from group 5 (decorative).
Decorative dahlias have fully double blooms showing no disc. The ray florets are generally broad and flat and may be involute for no more than 75% of their length (longitudinal axis) or slightly twisted, and usually bluntly pointed
That is a miniature Dahlia. Possibly the Decorative Dahlia Seduction. See BJY's answer for the details.