Star Trek: The Next Generation: Before Dishonor

An enemy so intractable that it cannot be reasoned with. The entire race thinks with one mind and strives toward one purpose: to add our biological distinctiveness to their own and wipe out individuality, to make every living thing Borg. In over two centuries, the Federation has never encountered a greater threat. Twice Starfleet assembled and threw countless starships to stand against them. The Borg were stopped, the price paid in blood. Humanity breathed a sigh of relief, assuming it was safe.