TMDb/Sullivan's Crossing Celebrity Sullivan's Crossing Season 4 premieres March 2026, but without Scott Patterson. Discover the cast shakeups, plot twists, and what's next for the hit series. May 3, 2026 AceShowbiz - Sullivan's Crossing has faced unexpected cast shakeups and intriguing plot developments, leaving fans wondering about the future of the popular series. Based on the novels by Robyn Carr, the show follows neurosurgeon Maggie, portrayed by Morgan Kohan, as she returns to her rural Nova Scotia hometown.