The DLC stars Agent Nico DaSilva as the protagonist rather than Agent Carter, taking place shortly before the events of the main game. DaSilva volunteered to be a part of a psychic experiment program at 'Hangar 6' - sometimes you just need the money.
As DLC lead designer Harley White-Wiedow notes, Hangar 6 R&D raises the difficulty level, but aims to balance this with abilities based on the 'Signal and Beyond' level in the game. Also introduced is the delicious-sounding Microwave Gun, along with a new AK-47.
The Bureau: XCOM Declassified (Hanger 6 R&D)