On April 27, 1986, at 12:32 AM Eastern Standard Time, a person calling themselves Captain Midnight was able to jam HBO's satellite feed, interrupting a broadcast of the Sean Penn/Timothy Hutton film The Falcon and the Snowman for more than two minutes with their own message complaining about their pricing structure for satellite dish owners. It was visible to more than half of HBO's total subscriber base at the time in the entire eastern United States.
In the mid-80s, HBO, Showtime, and The Movie Channel were the Big Three in the realm of premium cable services, still a new thing at the time, as television broadcasts had always been free over the airwaves before this. There was an independent community of satellite dish enthusiasts who were able to construct their own equipment and access premium services for free. This was a burgeoning industry, until HBO began scrambling its signal and charging dish owners $12.95 a month for subscriptions (which would translate to about $30/month today) despite the fact that they had to maintain their own equipment, or forcing them to buy their own descrambling technology for hundreds more. This caused a massive drop in dish sales and put many dealerships out of business.
Thus, the oddly polite protest message that interrupted their programming that night, over a standard color test pattern, simply read "Good Evening HBO From Captain Midnight. $12.95/Month? No Way! [Showtime/Movie Channel Beware!]" The disruption begins at about the 1:51 mark in this clip above.
The hijacking was eventually traced to John MacDougall, an engineer at Central Florida Teleport uplink station and owner and proprietor of MacDougall Electronics, one of those suffering dish dealerships who had lost a lot of money. He'd been inspired by the 1979 film about a pirate radio station called On the Air Live with Captain Midnight, and he had been vocal about protesting these practices — too vocal, it would turn out, as he was overheard bragging about the jamming into a payphone, which was the tip that led the FCC and FBI to him. He was fined $5k and put on a year's probation. His actions inspired a few copycats who likely saw him as a folk hero in the satellite community, but they also led to several new laws governing satellite uplinks, thanks to corporate lobbying and the omnipresent Cold War paranoia of the era.
Later, MacDougall would clarify his feelings about the incident in a statement. "I do not regret trying to get the message out to corporate America about unfair pricing and restrictive trade practices. That was the impetus for doing what I did; that's the reason I jammed HBO; that's the reason I sent them a polite message. What I do regret is that I was young and fairly naïve in the ways of the media. I didn't grasp the fact that no one understood my motives and that everyone would make assumptions. Had I known that up front I would have been much more fervent in explaining my motivations. I had no animus and I had no malice in my heart."
Andy Hunsaker has a head full of sitcom gags and nerd-genre lore, and can be followed @AndyHunsaker if you're into that sort of thing.