Miguel Nicolelis, a Brazilian neuroscientist, connects the brains of two rats directly, one in the United States and one in Brazil, wiring their neural signals together over the internet so that one animal's action triggers a matching response in the other. The pair succeed in syncing their responses in roughly seven out of ten attempts, a result Nicolelis lays out in his book Beyond Boundaries along with his prediction that a networked 'BrainNet' of linked minds is coming. Journalist Rob van Hattum travels to Sao Paulo to see the experiment firsthand, then crosses the Netherlands interviewing neuroscientists about where brain-reading technology is headed, at one point having his own brain scanned to test the limits of what can be extracted from it. Along the way the film shows quadriplegic patients operating robotic limbs through electrode implants and spinal injury patients using virtual reality to reactivate damaged senses. The throughline is a single question: once a brain's signals can be read and transmitted, how much of the mind stays private.