Saturday marks the 27th anniversary of one of history’s most bizarre and legendary acts of hacking: the Max Headroom Incident.

On the night of Nov. 22, 1987, WGN’s evening news was interrupted for about 25 seconds by a man dressed in a Max Headroom mask in front of a dizzying background. There was no audio beyond a jarring buzz, and as quickly as the incident began, it ended.

“Well, if you’re wondering what happened, so am I,” WGN sports reporter Dan Roan said with a nervous chuckle.

If it happened today, you wouldn’t be out of line thinking it was some sort of bizarre viral marketing stunt.

The hackers weren’t done. Two hours later, during an episode of “Doctor Who” on WTTW, “Max Headroom” was back, this time with sound.

“He’s a frickin’ nerd,” a distorted voice says before laughing.

The video goes on without much rhyme or reason. Chuck Swirsky is mentioned. Spanking and the “Clutch Cargo” theme song are involved. The transmission is interrupted, and two minutes later the Doctor is back.

“As far as I can tell, a massive electric shock,” the Doctor quips with impeccable timing. “He must have died instantly.”

This is how the Chicago Tribune reported the incident at the time:

Officials of the Federal Communications Commission were not amused as they searched Monday for clues to the identity of the pirate, who somehow managed to override the signals of two television stations in two hours.

[snip]

Television engineers speculated that the stations had been victimized by a practical joker with an expensive transmitter. They said it would take extremely high-powered equipment to squeeze out the microwave signals that carry the programs from the stations’ Northwest Side studios to downtown skyscrapers, where they are retransmitted to television sets throughout the Chicago area.

“You need a significant amount of power to do that,” said Robert Strutzel, WGN`s director of engineering, who was reluctant to discuss the prank in detail for fear of providing a ‘how to’ guide for others. “The interfering signal has to be quite strong.”

[snip]

Strutzel said an engineer quickly changed the frequency of the signal that was transmitting the news show to the Hancock building, thus breaking the lock established by the video pirate. Sports reporter Dan Rohn apologized for the interference and continued the sports report.

[snip]

“By the time our people began looking into what was going on, it was over,” said Anders Yocum, vice president for corporate communications at Channel 11. “Initially, we checked our internal video sources before thinking about something from the outside.”

How did it happen? Who was responsible?

That’s where the fun begins.

The working theory involves hackers working from the top of a tall building close to the Hancock building and Sears Tower, where WGN and WTTW broadcasted from. From there, the hackers blasted out their Max Headroom video and overwhelmed the studios’ signals. The operation involved extensive know-how of the sophisticated equipment used to broadcast television and an enormous amount of electricity.

It goes without saying that the FCC and FBI quickly got involved. Vice’s Motherboard took an extensive look at the incident and obtained the FBI’s report written by the FCC’s Field Operations Bureau assistant chief Dr. Michael Marcus. Motherboard’s story is worth reading in its entirety, but here’s a quick rundown of the investigation:

“I think the bad guy got close to the receiving end and just transmitted a signal that was received with a stronger strength than the more distant, intended signal,” said Marcus.

[snip]

“The background looked to be about eight-feet wide, industrial type metal, maybe a roll-down warehouse door,” he said. That would have already limited it to certain places in the city where the video could have been filmed. And one tip sounded particularly promising, said Marcus, one that pointed at a particular person, someone who worked for a company that had a warehouse-like space in the city, a place that might have played host to the video shoot.

[snip]

But even with a likely geographical location, Marcus said, finding the resources and manpower needed to continue the investigation was a struggle. He was back in headquarters in DC, and the FCC investigator in Chicago was too timid to go investigating.

[snip]

Momentum slowed: the case lacked evidence, and the threat felt ambiguous. “How are you going to lose sleep over something like that? Nobody dies, and there’s no damage.” There were fears at the time about the harm a satellite jammer might do to infrastructure that costs hundreds of millions of dollars, but concerns about regular television signals were much lower. “Max Headroom wasn’t a danger to public safety, or to a multimillion piece of equipment,” Marcus said. “So the resources were a lot less.”

Rumors and rampant speculation about the hackers’ identities have plagued the internet and its precursors for years. Those claiming responsibility range from performance artists to anonymous posters on 4chan, but the most likely scenario involves members of Chicago’s ’80s hacking scene.

The incident received renewed interest in 2010, when a thread was posted to Reddit with this straightforward title: “I believe I know who was behind the “Max Headroom Incident” that occurred on Chicago TV in 1987.”

The post was made by a still-active Redditor using the alias “bpoag” and supports the theory that those involved were members of Chicago’s hacker community. Of course, there is no way of knowing if there is any degree of truth to his post or if it is just incredibly detailed fan fiction. The poster offered no proof, just a compelling tale. It’s a fascinating contribution to the signal intrusion lore. Highlights from his story:

When I was in my early teens, a number of my friends were into the local phreaking/hacking scene. (This was suburban Chicago, from about 1985 until 1993 or so.) They were much older than me (high school and college age), but they put up with me as sort of a novelty I guess..They liked the fact I looked up to them as quasi-role models, at least.

[snip]

People who were into the hacking scene back then were basically the same type of people who are into the hacking scene now…Guys who live in their parent’s basements, charming/brilliant guys who don’t think to bathe often, and often lacking in social skills pretty much across the board. They hang out at Denny’s until they’re asked to leave, they can quote Monty Python sketches from memory, and sleep with JRR Tolkien books under their beds where other guys stash porn. Despite the lack of good grooming and social skills, there was the occasional party every so often, or at least a get together at somebody’s place.

[snip]

J was at the party in the apartment that afternoon. I didn’t talk with him directly (me, and the friend of mine that I was there with didn’t really talk to anybody that day), but I did overhear what the others were talking about. They were referring to J planning to do something “big” over the weekend. I remember that word, “big”, because it piqued my curiosity as to what might be considered “big” by their standards. I later asked them collectively during the dinner we all had at Pizza Hut later that night what they were talking about earlier, what “big” was, and someone (probably K) told me to “Just watch Channel 11 later tonight.” …As sort of an offhanded suggestion. I did happen to be watching Channel 11 later that night, having forgotten about the whole “big” conversation earlier that day. I saw it, but I didn’t put 2 and 2 together at the time.

He identified the two culprits by random initials, J and K. Of course, “JK” is internet slang for “just kidding.”

To this day, the person or persons responsible have not been identified.