A one-man show is normally a fairly straight-forward production,without a lot of complex personnel issues, but when that one man can’t go on, there’s a problem.

Actor John Rowan opened in the new Pegasus Theater production of John Sedaris’ “Santaland Diaries” as planned, on Dec. 5, but illness has forced him to drop out.

However, in true traditional show biz fashion, the show will run through Dec. 20 as originally  scheduled.  Mark Gregory will step into the role of cynical Crumpet the Elf, one of Santa’s helpers at Macy’s in New York, at 7:30 p.m. Friday and Saturday, Dec. 18-19. Donovan Dutro will star in the closing matinee, at 3 p.m. Sunday, Dec. 20.

All of the performances will be at the Sonoma West Inn and Spa, 14100 Brookside Lane, Guerneville. Admission: $15. Information, reservations: pegasustheater.com, 583-2343.