"The Status Quo Combustion" is the final episode of "The Big Bang Theory" Season 7. It is set to wrap-up with Sheldon checking out of Apartment 4A, as he faces an uncertain future.

 [Youtube/The Big Bang Theory]

In the previous episode, there were two major developments. Leonard and Penny got engaged and Emily and Raj kissed. The final episode is set to open with the announcements about the engagement and the kiss. The preview of the episode provides a glimpse of the happiness after Penny announces that she and Leonard are also engaged.

The preview also shows Penny breaking the news to her family about her engagement, and telling them that she is not pregnant. It looks like Penny is breaking her family's tradition of being pregnant at the time of engagement.

The spoilers leaked online and the preview clip reveal that Sheldon will find himself in a difficult situation because of Penny and Leonard's engagement and also due to other changes that is set to take place in the final episode of Season 7.

In the preview clip, Leonard can be seen asking Sheldon to move across the hall. He is suggesting that Sheldon move to Penny's place and he and Penny live at Apartment A4. According to the spoilers leaked online, Sheldon will be disturbed, wondering why Leonard is picking Penny over him. In addition to this, Caltech will stop him from changing his field of study, as the grant money is for string theory.

The spoilers also reveal that Stuart's comic store will catch fire and this will make Sheldon more frustrated. He will also not like the suggestion of Amy that they start living together. Unable to cope-up with all the changes, Sheldon will plan to leave Pasadena!

Sheldon will be leaving Pasadena to figure out things and to discover who he really is.

Meanwhile, Stuart will get hired as the caretaker of Howard's mother. According to the spoilers, Stuart and Howard's mother will get along, real well. Also, Raj and Emily will be taking their relationship to the next level, the synopsis of the episode indicates.

And, Amy will be seen hitting Leonard, because he allowed Sheldon to leave the town.