Before she took the name Janet Julian, she was known Janet Louise Johnson. She had done two TV appearances in 1973 when she was a kid, but in 1978 she replaced Pamela Sue Martin on The Hardy Boys/Nancy Drew Mysteries. It was a fine choice but unfortunately it was not meant to be. Janet Louise Johnson only got to be in four episodes of the show at the end of its second season. The producers chose not to feature a Nancy Drew character at all in the third season and the show ended afterwards. Would the show have survived longer if they had kept Janet L. Johnson on the show? It certainly couldn't have hurt. Unfazed, Janet went on to do a bunch of television guest appearances, changed her professional name to Janet Julian around 1980 and found some success on TV and in movies.
The following images are of Janet Louise Johnson in the 1978 episode 'Mystery on the Avalanche Express' of The Hardy Boys/Nancy Drew Mysteries: