Kudrow previewed Web Therapy's latest season in an interview with TV Guide, explaining that the story arc centres on self-centred therapist Fiona seeking help from her sister (Julia Louis-Dreyfus).
"Fiona sees her sister for therapy and her sister destroys her, but in an unobvious way," Kudrow revealed.
She further explained: "Fiona starts rethinking her whole life and the next time we see her she's in bed, in tears, no make-up, pyjamas - just a mess. And we've never seen her like that."
Kudrow went on to joke that Fiona's self-discovery is unlikely to help her become a better therapist or a kinder woman.
"This is who she is - a terrible person," the actress quipped.
Conan O'Brien, Meryl Streep, Molly Shannon and Kudrow's former Friends co-star David Schwimmer are all guest starring on Web Therapy's second season.
Schwimmer recently said that he was "really excited" to work with Kudrow again on the hit comedy series.
Web Therapy airs on Mondays at 11pm ET on Showtime.