In the show's recent season finale, it emerged that Penny and Raj (Kunal Nayyar) had spent the night together.
However, Cuoco confessed that she isn't sure what will happen next.
"Last season was crazy," she told Access Hollywood. "I think the writers have a lot of explaining to do. [Executive producer] Bill Prady said all the questions that you have will be answered, so that's a good sign."
Cuoco also revealed that she believes Penny and Raj did sleep together but added: "I don't know, maybe that'll change. It seemed that way, but you know TV, you never know what can switch around. But I know it's going to cause some strife between her and the guys."
Cuoco hinted that she doesn't think Leonard (Johnny Galecki) is "going to be very happy" but suggested that he is unlikely to become involved in a fight with Raj.
"It's so hard to get mad at little Raj," she said. "Maybe he will. Maybe there'll be some punching."
Nayyar has previously admitted that he was shocked by the twist, while Prady has suggested that the fling will have a big impact on Penny.
However, Prady has also hinted that the show will focus less on romantic storylines in the future.
The Big Bang Theory will return for a new season on September 22 on CBS.
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