The Big Bang Theory season 8 premiere airs tonight on CBS! Here’s everything you need to know about tonight’s brand-new back-to-back episodes.

A journey of self-discovery comes to an end, and friends find themselves feuding when The Big Bang Theory season 8, episodes 1 and 2 air tonight on CBS. The episodes, titled “The Locomotion Interruption” and “The Junior Professor Solution,” will kick off the new season with cars, trains, and unexpected educational responsibilities.

Drama!

The summary for “The Locomotion Interruption,” focuses on Sheldon’s return from last season’s ride-about – which does not seem to have ended on a high note.

“Leonard and Amy take an unexpected road trip to Arizona to pick up Sheldon,” CBS says. “Meanwhile, Penny interviews for a job at Bernadette’s company, and Howard is weirded out by Stuart’s relationship with Mrs. Wolowitz.”

Related: Brush up on The Big Bang Theory before the season 8 premiere

And the synopsis for “The Junior Professor Solution” doesn’t indicate that life back in Pasadena will be all Dr. Cooper hoped it would be.

“When Sheldon is forced to teach a class, Howard surprises everyone by taking it,” CBS writes. And as for the girls: “Meanwhile, the tension between Penny and Bernadette gives Amy a chance to play both sides.”

A new promo from CBS includes clips from The Big Bang Theory season 8 premiere, as well as commentary on upcoming developments from most of the main cast.

And we also see… rather a lot of Sheldon.

It certainly looks like strife will be central theme through the new episodes – though if recent clips from both “The Locomotion Interruption” and “The Junior Professor Solution” are any indication, hilarity is certain to ensue.

Still photos from The Big Bang Theory season 8 premiere offer more hints at what will develop tonight.

Oh, how we missed watching this geeky gang squabble. Never stop fighting, guys!

Where to watch ‘The Big Bang Theory’ online:

Catch The Big Bang Theory season 8 premiere on CBS.com. New (and old) episodes are also available for purchase on Amazon and iTunes.

The Big Bang Theory season 8 premiere airs tonight at 8:00 p.m. on CBS.

What are you most excited to see in ‘The Big Bang Theory’ season 8 premiere?