The 36-year-old has allegedly signed up for the Celebrity version in January, which is said to have left some superstars a little bit scared.
Among those he is thought to have dirt on are Kim Kardashian, Rihanna, Lady Gaga and Beyonce.
A source told the Daily Star: "Hollywood is the bitchiest place on Earth and Perez knows where the bodies are buried.
"He made his name sharing shocking or sleazy secrets about the stars. He was there when stars like Kim were starting out. It made him a lot of enemies, but a lot of money too.
"Perez knows he's famous for great gossip, and won't want to let viewers down."
According to reports, Lady Gaga in particular is worried about what Perez might say on the show and has apparently ordered her lawyers to watch.
They fell out in 2011, after she branded him 'fake' and he hit back, calling her 'fame hungry'.
Another insider said: "In the USA, the freedom of speech laws mean he can say anything.
"However, because UK libel laws are much stricter, Perez poses a problem when he talks about Gaga and any unfounded allegations. Channel 5 will have to keep a very tight rein on his comments."