The Big Bang Theory season 9
The Big Bang Theory season 9's official posterCBS

The Big Bang Theory season 9 has gone on a week-long hiatus and will return with an all-new episode on 10 March at 8pm EST on CBS Network. In episode 18 titled The Application Deterioration, Sheldon Cooper and his gang will try to patent their idea of Positive Negative Reaction.

The network has released the official synopsis for the episode, which reads as follows:

The boys will want to patent their idea and Sheldon is going to start drawing up a contract where they will split their share three ways. Meanwhile, The girls will end up talking about Bernadette's morning sickness and then hang out and head to the boys apartment. Raj is going to hear from both Emily and Claire.

The ninth season of The Big Bang Theory had a lot of milestone moment, with Sheldon and Amy finally having coitus, Howard and Bernadette expecting a baby and Leonard and Penny making their marriage work. Speaking about Sheldon and Amy's annual sex pact, showrunner Steve Molaro told TVLine: "Sheldon made it pretty clear that this would be an annual event on her birthday. I don't know what the future holds, but so far, he's been sticking to that."

The showrunner also confirmed that Leonard and Penny are not planning a baby anytime soon. According to Molaro, the newly-weds are in "no rush" to start a family and added: "Realistically, if Penny and Leonard had a baby, that baby would start to alter the DNA of the show a lot more dramatically than Howard and Bernadette's."

Until The Big Bang Theory returns on 10 March, you can catch up with the previous episodes of the hit CBS drama by clicking here (only in US).