Jon Wellner (born July 11, 1975) is an American actor, best known for his role as toxicologist Henry Andrews on '. He has portrayed Andrews from 2004 through to the 2015 season, his 11th with the show.
He began his affiliation with the show in season 4 as a researcher, verifying that the information on the show was accurate. He had a role as a zookeeper in season 5, then took on the role of Andrews. He continues to serve as a researcher for the show. In 2009 he and fellow cast member/researcher David Berman formed a company that does research for several other television forensics shows including Bones, ', and Drop Dead Diva.