The eighth season of the American sitcom The Big Bang Theory premiered on CBS with two back-to-back episodes on Monday, September 22, 2014. The series returned to its regular Thursday night time slot on October 30, 2014 beginning with the eighth season's seventh episode. The season concluded on May 7, 2015. On March 12, 2014, The Big Bang Theory was renewed for an additional three years, extending it through the 2016–17 television season for a total of ten seasons.
Mayim Bialik submitted the episode "The Prom Equivalency" for consideration due to her nomination for the Primetime Emmy Award for Outstanding Supporting Actress in a Comedy Series at the 67th Primetime Emmy Awards. Christine Baranski submitted the episode "The Maternal Combustion" for consideration due to her nomination for the Primetime Emmy Award for Outstanding Guest Actress in a Comedy Series at the 67th Primetime Creative Arts Emmy Awards.

Carol Ann Susi, the voice of the never-seen Mrs. Wolowitz, died of cancer at age 62 on November 11, 2014. In the season's fifteenth episode, "The Comic Book Store Regeneration", Howard Wolowitz receives a phone call that his mother died while visiting family in Florida.

Production
In February 2014, CBS CEO Leslie Moonves confirmed an eighth season, when announcing that the first part of the new season would air on a different night, due to CBS acquiring the rights to Thursday Night Football games. In May 2014, CBS announced at its annual upfront presentation, that the series would begin its eighth season on Mondays, before returning to the Thursday slot it has held since 2010 on October 30, once the football games end.

Delay
Production for the season was expected to begin on July 30, 2014, however the start was delayed due to the five main cast members' desire to renegotiate new contracts, with Johnny Galecki, Jim Parsons and Kaley Cuoco seeking approximately $1 million per episode, as well as more backend money. Simon Helberg and Kunal Nayyar negotiated together, separate from Galecki, Parsons and Cuoco's negotiations. Production was officially delayed on July 30, due to the contract negotiations, and was rescheduled for August 6, 2014. On August 4, Galecki, Parsons and Cuoco signed new contracts, worth $1 million per episode for three years, with the possibility to extend for a fourth year. The deals also include larger pieces of the show, signing bonuses, production deals and advances towards the back-end. The following day, Helberg and Nayyar renegotiated their contracts, giving them a per-episode pay in the "mid six-figure range", up from around $100,000 per episode they each received in years prior. The first table read for season 8 took place on August 6.
Premiere
The first episode of season 8, "The Locomotion Interruption", first aired in the United States on September 22, 2014. In Australia, season 8 premiered on October 13, 2014. In the United Kingdom, "The Locomotion Interruption" first aired on October 23, 2014.
Cast
Main cast
Johnny Galecki as Dr. Leonard Hofstadter
Jim Parsons as Dr. Sheldon Cooper
Kaley Cuoco as Penny
Simon Helberg as Howard Wolowitz
Kunal Nayyar as Dr. Rajesh "Raj" Koothrappali
Mayim Bialik as Dr. Amy Farrah Fowler
Melissa Rauch as Dr. Bernadette Rostenkowski-Wolowitz
Kevin Sussman as Stuart Bloom
Special guest cast
Billy Bob Thornton as Dr. Oliver Lorvis
LeVar Burton as himself
Nathan Fillion as himself
Kevin Smith as himself (voiceover)





