"The Big Bang Theory" Season 10 is currently looming in cancellation due to numerous reasons. On a lighter note, Raj's former girlfriends will be back in the series. Plus, the official plot description and promo clip of episode 13 'The Romance Recalibration' has been revealed by CBS.

Many fans are worried that their favorite show may not return to the television screen after "The Big Bang Theory" Season 10 gets over.

This is because "The Big Bang Theory" has not been renewed by CBS yet. There is no information as to whether "The Big Bang Theory" Season 11 would actually be produced or planned or not.

Add to that, series regular Jim Parsons was rumored to leave the show altogether because he already has a lot on his plate in the year 2017.

On the bright side, all of Raj's ex-girlfriends will officially return in "The Big Bang Theory" Season 10. Entertainment Weekly has learned that actresses Laura Spencer (as Emily), Alessandra Torresani (as Claire), Kate Micucci (as Lucy), Katie Leclerc (another Emily) will reappear in the February 2017 episodes.

As for the official plot synopsis of episode 13, Spoilers Guide notes, "When Penny (Kaley Cuoco) feels that Leonard Hofstadter is taking her for granted, she decides to go on a spa weekend with Amy Farrah Fowler (Mayim Bialik). Also, Howard Wolowitz (Simon Helberg) and Raj Koothrappali (Kunal Nayyar) try to fix a squeaky floorboard in the baby's room."

"The Big Bang Theory" Season 10 episode 13 is titled as "The Romance Recalibration". The upcoming episode is scheduled to premiere on Thursday, January 19, 2017, at 8:00 p.m. EST on CBS in the U.S. and channel 9 in Australia.

"The Big Bang Theory" is an American television sitcom created by Chuck Lorre and Bill Prady, both of whom serve as executive producers on the series.