"As far as I can tell, a massive electric shock. 
He died instantly." 

For explanation of post title, see 1:59 of the second YouTube clip

On the night of November 22, 1987, two Chicago television stations--WGN and local PBS affiliate WTTW--were hacked by an unknown party who managed to override the TV signals and break in with two separate pre-recorded segments that became officially known as "The Max Headroom Broadcast Signal Intrusion."

Here's a synopsis of the WGN hack (from wikipedia):

The first occurrence of the signal intrusion took place during then-independent station WGN-TV (channel 9)'s live telecast of its primetime newscast, The Nine O'Clock News (now known as WGN News at Nine). During Chicago Bears highlights in the sports report, the screen went black for 15 seconds, then returned with a person wearing a Max Headroom mask,^[1] moving around and jumping. His head was in front of a sheet of moving corrugated metal, which imitated the background effect used in the Max Headroom TV and movie appearances. There was no audio other than a buzzing noise. The hijack was stopped after engineers at WGN switched the frequency of their studio link to the John Hancock Center transmitter.^[2]

The incident left sports anchor Dan Roan bemused, saying, "Well, if you're wondering what's happened, so am I."

Pt. 1 -- The brief interruption on WGN during the evening news

And then later that same night, during a showing of Doctor Who on the Chicago PBS station....

Doctor Who was interrupted by television static, to which an unidentified man appeared, mentioning about WTTW pundit, Chuck Swirsky, saying he is better than him. The man started to moan, scream and laugh. He continued to laugh and utter various random and unrelated phrases, including New Coke's advertising slogan "Catch the Wave" while holding a Pepsi can (Max Headroom was a Coca-Cola spokesperson at the time), then tossing the can down, leaning towards the camera and giving the finger wearing a rubber extension over his middle finger, although it was hard to see the gesture. He then retrieved the Pepsi can, and saying "Your love is fading", before removing the rubber extension, then began humming the theme song to Clutch Cargo* saying "I still see the X", which referred to the final episode of the series, before resuming humming again. He then began to moan painfully, exclaiming about his piles (a reference to a Preparation H commercial), to which an indistinguishable flatulence sound is heard. He then stated that he had "made a giant masterpiece for all the greatest world newspaper nerds" (the WGN call letters used by the Chicago television station as well as its sister radio station are an abbreviation for "World's Greatest Newspaper", in reference to the flagship newspaper of their corporate parent, the Tribune Company's Chicago Tribune). He then held up a glove and said, "My brother is wearing the other one," and he put the glove on, commenting that it was "dirty" and that "it's like you got blood stains on it!" He then threw the glove down in disgust.

The picture suddenly cut over to a shot of the man's lower torso. His buttocks were partly exposed, and he was holding the now-removed mask up to the camera (with the rubber extension now placed in the mouth of the mask), howling, "They're coming to get me!" He then said, "Come get me, bitch!" An unidentified accomplice wearing a French maid outfit** then started to spank the man with a flyswatter as he screamed loudly. The transmission then blacked out for a few seconds before resuming to Doctor Who in progress; the hijack lasted for about 90 seconds.^[3]

* a weird 1960's cartoon, popular with stoners

** actually it was a cowgirl/Annie Oakley costume

Pt. 2 -- The more famous one, a longer clip (the one with audio), 

aired in the middle of a Doctor Who episode

ALSO, some of the subtitles are inaccurate: "Max" didn't say "I stole CBS," 
he said "I still see the X" (Clutch Cargo reference) and at one point 
he says "My piles!" not "My files!"

As it happened, I remember the incident well. I was actually in Chicago at the time, visiting my Dad for Thanksgiving week. Although I grew up in Indianapolis full time, I spent most holidays and about a dozen weekends a year in the Windy City. My Dad worked for an advertising agency on Wacker Dr. (heh heh, "wacker"), from 1985 - 1991 and he lived in a high rise on Diversey Pkwy, across the street from Lincoln Park.

Dad's old digs. I love that neighborhood and make a point
to pay my respects whenever I pass through the city. 

I didn't see the clip when it originally aired that Sunday night, but I saw the aftermath. My Dad always had the news on during the evenings, so in the following days we got to experience all the brouhaha and the media reports over "the television piracy." 

Here's a compilation of clips covering the incident:

My favorite part of the above video comes in at the 4:00 mark, with the incensed Doctor Who fan moaning in a thick Chicago accent, "We're gonna have to tape ooooh-ver it." It's funny, you'd think of all people, Whovians would appreciate being the first to see something bizarre and unexpected coming over the airwaves, but I also see why they would have been pissed off. In 1987, you didn't have instant access to any television clip you wanted to watch. You weren't spoiled by things like On Demand and YouTube. Doctor Who was more of a cult thing back then--definitely not as mainstream as it is today--so if you wanted to see The Doctor you really were at the mercy of the local PBS affiliate (and your VCR, apparently). In fact, the main reason why the Max Headroom pirating was able to gain legendary status in the pre-internet days was most likely because of the fans who were taping the episode, inadvertently preserving an infamous bit of broadcast television trollery in the process.

It's not hard to see why the FCC was nervous; obviously the persons responsible for carrying out the signal intrusion knew what they were doing and had access to fairly sophisticated broadcast equipment. These weren't your garden variety pranksters; if they were able to shanghai a newscast and an episode of Dr. Who with footage of some guy dicking around with a rubber mask, a flyswatter and little PG-13 bare-assed S + M, who knows what else they were capable of? What if they broke into an episode of This Old House and subjected innocent DIY enthusiasts to full-on penetration porn? Or what if--God forbid--the bastards used their evil to sabotage Moonlighting?

Bur aside from the FCC and television news, I don't remember much panic among the general public. There was a lot of head-shaking and a general attitude of "those darn hooligans better watch out!" but there was none of the "Oh my God, they're terrorists!" reaction you might get if it occurred today.

There have been countless online articles and blog posts written about the incident, and the video clips have racked up millions of views on YouTube. Over twenty-five years later, the prevailing attitude reflected in the YouTube comments (and some of the internet think-pieces) seems to be one of "OMG this is so fucking creepy!" I don't disagree with that sentiment, but IMHO the first WGN clip featuring the random Max Headroom head bobbing around the screen with the background buzzing noise is 100% creepier than the second interruption. If the hackers had stuck with the first intrusion and then faded into the ether, I think I'd have been sufficiently freaked out for the rest of my life. But coming back two hours later and goofing off with a Pepsi can, complaining of hemorrhoids and getting spanked by a fly swatter sort of negates the creepy momentum they had going with that first appearance.

The other thing that strikes me about the news coverage of the signal intrusion is how sure everyone was that the "pirates" would be caught. The fact is, the hackers were never caught or identified, and that makes it even more intriguing. 

Amazingly, in 2010 a guy on reddit claimed to know the duo behind the hacking. He has no real proof, but he's got some amazing insights. If he is telling the truth about being peripherally involved in the hacking/phreaking community in Chicago at the time, I'm inclined to believe that the two brothers he talks about are the culprits, The most telling clue is his revelation that the brother with autism (the one in front of the camera) had a habit of saying "Oooooh," (instead of "um," for instance) during pauses in conversation, something that rubber mask Max Headroom does frequently throughout the broadcast.

I hope that they never fully uncover the real story behind the Headroom hack. In this day and age of internet hoaxes and blatantly scripted "reality" TV and beloved icons being outed as cheaters and sexual predators, it's kind of comforting to have this bit of mystery that's managed to survive the internet age. The MHBSI stands out as a whimsical, bizarre little puzzle that can be endlessly debated and analyzed, but never understood.

And I kinda dig that.

CATCH THE WAVE!