Netflix’s Mindhunter seems to be the service’s next big breakout in terms of original programming; the grisly, David Fincher-directed story of the FBI’s mid-’70s series of interviews with convicted, imprisoned serial killers, which formed the early basis of the bureau’s criminal profiling programs. It only takes one look at Mindhunter to see just how disturbing the show is capable of being, recalling the extreme tension of Fincher’s earlier work on the film Zodiac, but now we have an even more disturbing side-by-side video that confirms just how realistic Mindhunter is to these real conversations.

Videographer Thomas Flight has given us an interesting look inside the Mindhunter interview of serial killer Ed Kemper in particular. Using real-life footage of the interviews the FBI conducted with Kemper, Flight synched up the killer’s answers with the depiction of similar (or even the exact same) questions on Mindhunter. Suffice to say, the results are chilling, and you can watch them via the YouTube player above.

Much of this has to do with the shocking nature of Kemper’s crimes themselves. An abnormality even among serial killers, Kemper is large, imposing but very intelligent and well spoken. Supposedly boasting an IQ of more than 140, he was first imprisoned as a teenager for killing his grandparents at the age of 15. After convincing the state of California of his rehabilitation, however, Kemper was released back into society in his 20s, where he embarked on a spree of killings that involved female hitchhikers, and eventually his own mother. The details are grisly, and we don’t need to go into them here.

What we should note is the masterful performance by actor Cameron Britton as Kemper, somehow conveying both the killer’s cunning, intelligence and supposed regret for his actions. It’s disarming how convivial he sounds—like a guy you might meet on the stool next to you at a bar, and spend the night chatting with. Truly, a disturbing real-life story, and a brilliant portrayal by Britton and Fincher as director.

Mindhunter is currently available via Netflix, and makes for some pretty obvious pre-Halloween viewing.