Karen Prell is best known as the performer of Red Fraggle in Fraggle Rock. She also performed some characters in other Jim Henson films, and has enjoyed a significant second career as a computer animator for such studios as Pixar and DNA. In Sesame Street, she performed Deena Monster, which was a background character in the classic Sesame Street. Her website includes notes about working with Jim Henson and pictures of her custom puppets.
Prell currently works as an animator with Valve Corporation.[1]