"The Big Bang Theory", an American TV series created by Bill Prady and Chuck Lorre, has surprised its fans with actor Billy Bob Thornton as the major guest.

"The Big Bang Theory" has moved back to Thursday night with a miracle as it was able to keep the surprise cameo under the wraps ahead of airing, which is an act that nearly unheard of in an age where the spoilers can leak way before the episodes debut.

The CBS TV series has welcomed Billy Bob Thornton, an Oscar winner, who played as Dr. Oliver Lorvis, the urologist who misunderstands the flirtation of Penny while working as well as attempts to woo her.

According to Entertainment Weekly, Steve Molaro, the showrunner of the TV series, several months ago, they had seen an interview with the actor talking about the shows he like. Thornton mentioned how much he liked "The Big Bang Theory" and watched it all the time. This is why Molaro thought that he was cool and great to be part of the TV series.

The producers started with the thought of Penny taking off her own engagement ring while she is working as the pharmaceutical representative to increase her sales. Molaro said that when they thought about Billy Bob, they imagined that he can be the doctor who does not quite understand the signals, which could be an awkward doctors who falls for the sales flirtations of Penny. Billy Bob thought that the concept is great and that's why he became a guest in the TV series.

"The Big Bang Theory" airs every Thursday at 8pm on CBS.

In other news, Latin Post reported that Thornton broke his silence and spoke about his married life with Connie Angland, his wife. The actor married Angland in October 2014.