The mask worn by the figure in the video was from the short-lived 1980s science fiction series, Max Headroom. Max Headroom was the lead character of the show who was portrayed as the first computer-generated TV host who reported the news from the future.
These successful television hacks quickly gained much attention from the public. Within hours of the incident, federal officials were called in to investigate these unusual broadcast intrusions. With "hacking" being a relatively unknown term in 1987 and the before days of the internet, officials were left clueless about who/what/how/why this happened. The pranksters were never found but their legacy lives on.