PORTLAND — Portland author Sarah Thomson will be share her vampire expertise on the Travel Channel show “Monumental Mysteries.”

The show premieres at 9 p.m. on May 9 on Travel Channel.

Thomson is the author of “Mercy: The Last New England Vampire.” She was filmed earlier this year at the Rhode Island gravesite of Mercy Brown, to talk about the purported vampire, who died in 1892.

Thomson’s book was published in 2011 by Maine-based Islandport Press.