In the near future, people's brains are directly connected to The Feed. Every interaction, every emotion, every memory can be shared instantly.
Tom and Kate, a millennial couple, are trying to resist their addiction to The Feed. Toms father invented The Feed, but Tom fears it, especially when he learns of his father's plans to expand it. Then, something or someone starts accessing people's minds through The Feed and "taking" them over.
People's loved ones wake up as someone else, someone who wants to kill them.