Olympics Opening Ceremony Features Headless Marie Antoinettes in Gruesome Skit

The Olympics opening ceremony kicked off with one of its wildest starts ever -- a castle full of beheaded Marie Antoinettes rocking out to heavy metal ... and boy, was it a sight.

The performance over in Paris Friday was electrifying -- heavy metal band Gojira teamed up with opera singer Marina Viotti to kick things off for a head-banging revolution ... while all the Marie Antoinettes sang along to the famous revolutionary song "Ah! Ça Ira!"

Red fireworks -- meant to symbolize blood, of course -- shot into the sky ... while actual fire and each band member staggered onto a different windowsill brought the performance to life.

There were multiple Marie Antoinettes in each window -- and yes, they were all beheaded ... obviously touching on the French Revolution and all the heads that rolled back then, including hers.

Overall, the performance was a tribute to Paris' political evolution and emancipation over time -- which is fine ... but, it was graphic ... especially for day-time TV. Anyway, they went there.

Goes without saying, it was a big moment for the French band Gojira ... who made history as the first rock metal band to perform at the Olympics -- and they rocked out hard to ring in the big moment.

They already have a humongous fan base and three Grammy noms, so this is just the cherry on top of their incredible career -- especially in their native France.