Crazy On You: Watch Heart's explosive television debut on The Midnight Special in 1977

As American TV viewers sat down to watch long-running music show The Midnight Special on March 4, 1977, they were about to watch something no television viewer had ever seen before: a group of rising stars from Seattle called Heart.

The band's debut album Dreamboat Annie had been released in August 1975 by Canadian label Mushroom – the band were based in Vancouver, BC during their early years – but it was a slow burner: it took a full year to enter the Canadian charts, and wouldn't reach the US chart until October 1976.

By the time Heart's first TV show was booked, album number two was about to come out. Little Queen would arrive in May 1977 (although Mushroom trumped it with an unfinished second album, Magazine, the previous month), but their Midnight Special set would only feature songs from their debut. After an awkward introduction from host Harry “KC” Casey of KC and the Sunshine Band, the band played Magic Man, Dreamboat Annie (Fantasy Child), Crazy On You and White Lightning And Wine.

High quality footage of Crazy On You – originally released as Heart's debut US single in March 1976 – has just been made available on The Midnight Special's increasingly vital YouTube channel, and it finds the band in blistering form from the very first moments, as guitarist Nancy Wilson plays the song's familiar acoustic intro.

“I wanted to write an acoustic guitar intro before the song started,” Wilson told Classic Rock. “So I sat for a few days, just trying to channel that first bar. I wanted it to be really memorable. It was the hardest part, finding a way in. But now, every time I play the introduction, everyone recognises it right away."

The main part of the song kicks into life, with singer Ann Wilson's vocal sounding a little thin despite clearly firing in all cylinders – you can blame the TV mix for that – and the rest of the band (guitarist Roger Fisher, guitarist/keyboardist Howard Leese, bassist Steve Fossen and drummer Michael Derosier) are similarly on point. Fisher adds some real fire to the performance, and appears to have come to the party dressed as Luke Skywalker (perplexingly, Star Wars wasn't released until two months later).

We don't know if fellow guests Jose Feliciano and Gordon Lightfoot exchanged acoustic guitar tips with the younger Wilson sister, but older sister Ann has continued to sing Crazy On You with the same commitment she showed on The Midnight Special.

"After many renditions, it’s still satisfying because there’s no bullshit in that song," she told Classic Rock. "The words still resonate because I still feel the same way about the world. The song gave a lot of people hope, because they would look at the challenges and difficult things in their lives and think, ‘The world is really screwed up but I have this person who loves me,’ and that’s what the song is really all about."