While Pratt and Faris are clearly meant to be in real-life, their on-camera romance might not last forever. According to an episode synopsis, Bonnie (Allison Janney) encourages Christy (Faris) to pursue Marjorie's charming nephew, Nick (Pratt), despite the fact that he's been declared off limits.
Pratt's appearance on Mom will air Thursday, Jan. 19, at 9 p.m. ET/PT on CBS.
The couple last shared the screen in 2012's Movie 43, and though Pratt revealed during a Reddit AMA in December that the two would act together again, Faris told ET in 2014 that she would "love" to have her husband on Mom.
"Oh my god, I would love it so much," she said at the time. "I know that he would love it because we're both hams, we're actors. But the multicam format really lends itself just to that element of performing live is so thrilling. So I'm going to get him. I'm going to get him."