The Big Bang Theory Season 8 Premiere

The eighth season of The Big Bang Theory premieres tonight on CBS with two, back-to-back episodes titled "The Locomotion Interruption" and "The Junior Professor Solution."

In "The Locomotion Interruption," Leonard and Amy take an unexpected road trip to Arizona to pick up Sheldon. Meanwhile, Penny interviews for a job at Bernadette's company, and Howard is weirded out by Stuart's relationship with Mrs. Wolowitz.

In "The Junior Professor Solution, when Sheldon is forced to teach a class, Howard surprises everyone by taking it. Meanwhile, the tension between Penny and Bernadette gives Amy a chance to play both sides.

CBS has released two preview videos, included below:

The Bang Theory Season 8 premiere airs September 22, beginning at 8 p.m. ET/PT on CBS.