The Big Bang Theory, The Birthday Synchronicity

In the Season 10 premiere, the gang deals with the awkward aftermath of an overnight liaison between Sheldon's mother and Leonard's father. Meanwhile, Penny's dysfunctional family is in town for the wedding.

The guys heads are in a spin when an Air Force bigwig approaches them about their revolutionary gyroscope invention, and Bernadette is upset with Penny after she accidentally leaks a secret to the mum-to-be's coworkers about her being pregnant.

Howard and Leonard are putting in late nights at work and Sheldon is having trouble keeping up, Raj and a pregnant Bernadette spend a day together, and Penny and Amy take in a faculty party.

Sheldon and Amy decide to move in together when her apartment floods. Meanwhile, Howard and Bernadette become upset when Raj learns the gender of their baby before they do.

Amy and Sheldon's live-in relationship may be in the toilet after he accuses her of not following the bathroom schedule. Meanwhile, Howard and Bernadette's secret staycation is interrupted by interfering interlopers who are sneaking into their hot tub.

Feeling his fetal offspring kick sends Howard on a baby-items buying binge with Raj, Sheldon and Amy host a brunch in their new digs, and Penny, by virtue of her virtuoso performance in 'Serial Apist,' is invited to a sci-fi convention.

In order to remain Sheldon's roomie, Amy fibs about repairs being made to her apartment. Later, they present an episode of 'Fun with Flags' in Penny's apartment.

A successful gene experiment leaves Sheldon excited to procreate with Amy, and he pulls out all stops to get her on board. Meanwhile, Raj is reluctant to reveal what the new woman in his life does for a living.

A geologist coworker's MacArthur Genius fellowship award leaves Sheldon stone cold jealous. Meanwhile, Howard stumbles upon a remote-control Stephen Hawking action figure that he invented. Hawking appears as himself.

A great divide develops between Sheldon and Leonard when it comes time to divvy up their shared belongings. Meanwhile, with Bernadette heading into her pregnancy homestretch, Raj and Stuart battle to be the one providing her the most help.

The Wolowitz baby arrives, while Sheldon and Amy celebrate Amy's birthday.

Sheldon and Amy visit Leonard and Penny for the first time since the holidays and share details about their terrible trip to Texas.

After a marital disagreement, Penny takes off for a spa weekend with Amy, and Sheldon steps in to play peacemaker for the squabbling newlyweds. Meanwhile, Howard and Raj do battle with a noisy floor in the baby's room.

Sheldon decides to test an MIT invention that can help read people's emotions. Meanwhile, Leonard has trouble hiding his emotions when Penny announces her brother is going to visit, and Raj gathers former girlfriends to ask for their dating advice.

With Sheldon hindering progress on the guidance-system project, Leonard and Howard figure the only way they can get back on track is to engineer a distraction by getting him tickets to a historic railroad.

Amy is incensed when she discovers Sheldon has shared intimate relationship information with people at the University, and Raj is knocked for a loop when his father stops sending financial support.

Without financial backing from his father, Raj finds himself in a cash crunch and turns to Sheldon to help him get his head above water. Meanwhile, Penny considers crashing the guys' annual Comic-Con getaway.

Leonard and Penny offer Sheldon's old room to Raj after he moves out of his apartment.

Raj moves in with Leonard and Penny and a period of adjustment begins for the three, while usually self-centered Sheldon shows surprising interest in Amy's work.

Sheldon is working overtime and pushing himself when he collaborates on projects with Leonard and Howard, and another one with Amy, all on the same day. Bernadette's maternity leave is running out and she must face going back to work.

Leaving baby Halley in day care proves to be tough for Bernadette after she starts back to work, and geologist Bert digs up a girlfriend, but some of his colleagues think she's a gold digger.

Penny's job offer from a former boyfriend doesn't sit well with Leonard.

Leonard, Sheldon and Wolowitz celebrate the successful completion of their top-secret military project, until an unpleasant surprise leaves their heads spinning. Amy considers an offer of a summer position as a visiting researcher.

On the Season 10 finale, Sheldon's former admirer, Dr Ramona Nowitzki, turns up while Amy is visiting Princeton, and the gang is extremely concerned.