'Big Bang' On Last Legs After Ratings Disaster: What Tore The Show Apart

There's a mutiny brewing on The Big Bang Theory — with massive egos, raging jealousy and ugly backbiting tearing the show apart, RadarOnline.com has learned exclusively!

Tensions have exploded as season 11 of the sitcom recently scored its lowest ratings ever, and sources dish the long-running CBS hit may be on its last legs!

"Many of the cast members have gotten swelled heads, and some of the other actors aren't happy about it," tattled a show insider.

Sources at the show and CBS have told RadarOnline.com the series will end after season 12 as some cast members are itching to get out — despite their million-dollars-an-episode paychecks !

Jim Parsons — a four-time Emmy winner for playing mega-geek Sheldon Cooper — already narrates the spin-off, Young Sheldon.

But the gig's got co-stars Kaley Cuoco and Johnny Galecki — who play Penny and Leonard Hofstadter — in a tizzy! "It's no secret Kaley thinks of herself as the show's big draw," spilled one insider.

Johnny is reportedly "silently simmering" over Jim's big-dog status as TV's highest paid star — with a whopping $27.5 million a year!

Network honchos soothed Johnny's ruffled feathers when the new comedy he's producing, Living Biblically, was slated for a mid-season premiere in February.

"Jim and Johnny both have wealthy new deals now," noted a source, "and that's turned a lot of the others off!"

We pay for juicy info! Do you have a story for RadarOnline.com? Email us at tips@radaronline.com, or call us at (866) ON-RADAR (667-2327) any time, day or night.