He should have put a ring on it. Sheldon (Jim Parsons) had plans to propose to Amy (Mayim Bialik) in the Season 8 finale of “The Big Bang Theory,” but they were spoiled when Amy beat him to the punch with a surprise break-up. How long had Sheldon been planning to propose? Showrunner Steve Molaro says the Season 9 premiere will get fans up to speed.

Molaro said the season premiere will delve into the backstory of Sheldon’s almost-proposal.

“You will learn more about the ring: how long he's had it, and what his mindset about it at the moment is,” Molaro told the Hollywood Reporter, adding that Sheldon will not be coping with the split too well. “He is a man of science and he's been presented with a problem that he can't just think of a solution for. And it's very frustrating. He doesn't immediately turn to anyone for support; instead, he is going to pursue Amy. His thought processes can get pretty misguided in that that he thinks, ‘Oh, this will make her jealous and make her like me again,’ but that will only make her furious. He's not good at leaving her alone. The one thing she asked for was a little bit of time to think and he's not going to give that to her.”

While Sheldon will be trying to salvage a possible engagement, Leonard (Johnny Galecki) will be trying to make things right with his own fiancé. In the Season 8 finale, Leonard confessed to Penny (Kaley Cuoco-Sweeting) that he had kissed someone else earlier in their relationship. He wanted to have no secrets going into their marriage, but the confession had Penny doubting Leonard's commitment. Then, the show teased the appearance of the girl behind the mystery kiss, Mandy, in Season 9, causing fans to fear that the couple could end their engagement.

Watch the promo for “The Big Bang Theory” Season 9 below:

Will Sheldon be able to win Amy back? Fans will have to wait to find out. “The Big Bang Theory” Season 9 premieres Sep. 21 at 8 p.m. EDT on CBS.