Hawaii Five-O type TV Show network CBS

Another Lost vet is set to pop up on Hawaii Five-0: William Mapother, who played creepy island resident Ethan Rom, will guest-star in an episode of the CBS police drama, EW has learned.

Mapother—who has recently popped up on shows including The Mentalist, Mad Men and Castle—will play Eric Porter, a likable, wealthy business owner who gets entangled in a painful and tense situation but offers his help to the authorities. His episode is slated to air sometime this fall.

Mapother represents the ninth (!) Lost alum to appear on Hawaii Five-0. The others (not The Others) are Daniel Dae Kim, Terry O’Quinn, Jorge Garcia, Henry Ian Cusick, Sam Anderson, Tania Raymonde and François Chau.