Gretchen aka The Gretch is a girl who is described as being anything but "sugary sweet", she is sardonic and indifferent about everything. Her lack of enthusiasm is made up with her sharp, critical tongue. With a black belt in karate and an intolerance toward wrong doing, Gretchen is not a girl you want to mess with. However, underneath the tough exterior, she has a huge heart and secretly wishes she could be like any normal girl (though she would never ever reveal this).
Her catchphrase is "Ya think?!" usually said to McGee when a plan has gone wrong and he points out the obvious. She is revealed to have a severe phobia of chipmunks in "Cheeks of Dread" and is allergic to lizards and dragons, shown in "How to Potty Train your Dragon".