Mark Hapka is an American film and television actor who first gained attention for portraying the lead role of the spirit 'Zach' on the Ghost Whisperer spin-off Ghost Whisperer: The Other Side. Hapka is most notable for his previous role as Nathan Horton on the NBC soap opera Days of Our Lives.

Ghost Whisperer is an American supernatural television series, which ran on CBS from September 23, 2005, to May 21, 2010.