After an accident, Juliette demanded Nick tell her what was really happening, but before he had the chance to, she fell into a coma, with half of her memories being erased by Nick when she eventually awoke.
Elizabeth Tulloch’s Juliette was the girlfriend of Nick Burkhardt, the titular Grimm in the show of the same name.
Just imagine how much more she could have helped if Juliette had just been clued in on everything from the get-go.
He kept hidden the secret of who he really was: a descendant from a line of hunters who fight supernatural forces.