Robin Mattson and Parker Stevenson in The Hardy Boys/Nancy Drew Mysteries (1977)

Shaun Cassidy and Parker Stevenson in The Hardy Boys/Nancy Drew Mysteries (1977)

Maud Strand in The Hardy Boys/Nancy Drew Mysteries (1977)

Shaun Cassidy in The Hardy Boys/Nancy Drew Mysteries (1977)

The Hardy Boys/Nancy Drew Mysteries (1977)

Pamela Sue Martin in The Hardy Boys/Nancy Drew Mysteries (1977)

"The Hardy Boys Mysteries" Shaun Cassidy, Parker Stevensen circa 1977

THE HARDY BOYS/NANCY DREW MYSTERIES - "The Mystery of the Hollywood Phantom" which aired on October 2, 1977.

Shaun Cassidy, Pamela Sue Martin, and Parker Stevenson in The Hardy Boys/Nancy Drew Mysteries (1977)

Casey Kasem, Pamela Sue Martin, and Parker Stevenson in The Hardy Boys/Nancy Drew Mysteries (1977)

Shaun Cassidy and Diana Muldaur in The Hardy Boys/Nancy Drew Mysteries (1977)

Ruth Cox and Shaun Cassidy in the Nancy Drew Hardy Boys series.

Ruth Cox playing "Bess" Nancy Drew's Cousin with Pamela Sue Martin

Shaun Cassidy, Ed Gilbert, and Parker Stevenson in The Hardy Boys/Nancy Drew Mysteries (1977)