The fan-favorite characters are summoned back to the canvas by Ridge (Thorsten Kaye), who feels he needs reinforcements to help convince his father, Eric (John McCook), that the patriarch's frowned-upon relationship with Quinn (Rena Sofer) is a huge mistake.
Soap Opera Digest reports Harmon will hit the canvas on Wednesday, September 21, and Kay will follow one day later, on Thursday, September 22. There's no word yet on whether the pair's return will be short-lived or long term -- or whether or not the characters will be successful in thwarting Eric and Quinn's budding romance.
Harmon was last seen on B&B in July 2015, while Kay made her last appearance in August 2014.
What do you think about Harmon and Kay returning to B&B? Would you like to see the characters stick around long term? We want to hear from you -- and there are many ways you can share your thoughts.