Rob Mac and Kaitlin Olson were spotted running through Los Angeles streets while filming scenes for the upcoming 18th season of FX’s It’s Always Sunny in Philadelphia on June 17.
Rob Mac and Kaitlin Olson looked like they were moving at full speed through Los Angeles—right in the middle of filming It’s Always Sunny in Philadelphia’s upcoming 18th season.
The married co-stars were photographed running together on Wednesday, June 17. Rob, 49, was seen carrying a black fuzzy hat, while Kaitlin, 50, held on tight to a jug filled with an orange liquid, taking occasional chugs as they filmed scenes outside.
Fellow cast member Glenn Howerton was also on set and appeared to be directing the moment as the comedy continues building toward its next chapter.
It’s Always Sunny in Philadelphia first premiered in 2005. and the series has stayed a staple of American comedy for years. When season 15 premiered in December 2021, the show became the longest-running American live-action sitcom in terms of total seasons. The most recent season—season 17—aired in the summer of 2025. and as of now. season 18 does not have a premiere date.
Back on the show’s timeline, Howerton previously talked about why he seriously considered walking away from It’s Always Sunny in Philadelphia during an interview last year, adding another layer of tension to the idea of what keeps the series going after all these seasons.
For now, the only certainty is that the cast is still in motion—literally—out on the streets while filming the next season, with fans waiting to see when season 18 will finally land.
Rob Mac Kaitlin Olson It’s Always Sunny in Philadelphia Season 18 FX comedy series Glenn Howerton Charlie Day Danny DeVito Los Angeles filming