'The Big Bang Theory' season 12 finale spoilers, plot news: Sheldon's mom, Leonard's dad hook up; Leonard, Penny tie the knot once more

Hit CBS sitcom "The Big Bang Theory" will have its season 9 finale next week, and rumor has it that the series will end on a major cliffhanger.

According to spoiler reports, episode 24 will feature Leonard's (Johnny Galecki) father for the first time. Dr. Hofstadter will be played by Judd Hirsch, who Galecki personally asked to be on the show to play the part of his father. In the finale titled "The Convergence-Convergence," Sheldon's (Jim Parsons) mother Mary Cooper will meet Leonard's father and they eventually hook up. They might be an odd couple, but Leonard's father is already divorced while Sheldon's mother is a widow.

Additionally, the episode will also see Penny and Leonard get married once again. This time, their family and friends are present to witness their union, as they previously eloped and no one got to see them in a formal wedding ceremony. Meanwhile, Beverly and Mary butt heads as their conflicting beliefs cause a fight between them. Fans are well aware that Beverly is a firm believer of science while Mary is a devout follower of Jesus Christ.

On another note, showrunner Chuck Lorre previously talked about the latest addition to their cast, Leonard's father. "We talked about Leonard's father being a very different kind of character than his mother," he told Entertainment Weekly. "When you look at Leonard and his mother, and how different Leonard is, well the other piece of the equation is his dad, so you can imagine the space that character has to occupy and who he'd have to be to get a Leonard out of the equation."

The official synopsis for the season 9 finale reads:

"Leonard and Penny get remarried in front of their friends (who show up), Leonard's parents and Mary Cooper. Sheldon's mother and Leonard's father find something in common. Howard gets an unknown email from the Air Force about his invention."

Stay tuned for the last two episodes of "The Big Bang Theory" which airs  Thursdays at 8 p.m. EST on CBS.