The Vanishing Shadow (1934) is a Universal science-fiction film serial directed by Lew Landers. The serial features what is believed to be the first appearance of a hand held ray gun in film.

Plot
Stanley Stanfield is the inventor of the Vanishing Ray, a wearable device which, when active, leaves only the user’s shadow still visible. After meeting with a fellow scientist, Carl Van Dorn, a prototype is built. Stanley intends to sell bonds to finance his invention. He inherited them from his late father, an editor for the Tribune newspaper, but the stockbroker he meets is corruptly involved with Wade Barnett, the businessman who hounded Stanley’s father to his death. Barnett wants the bonds and will go to any length to acquire them. A conflict ensues between Stanley and Barnett. However, Stanley’s new girlfriend, Gloria Grant, is really Gloria Barnett, his enemy’s estranged daughter. Neither hero nor villain wants to hurt Gloria and must work around this in their struggle. Many science fiction gadgets, including a robot and The Destroying Ray, also feature.

Dorgan, Barnett’s “spear-point heavy”, is unhappy with having to hold back to protect Gloria. Eventually he captures both Stanley and Gloria but blackmails his boss to ensure her safety. Barnett turns up with both the ransom money and the police but he is shot in the fight. Before dying, he makes his peace with his daughter. Gloria and Stanley finally marry and take over operation of the Tribune.

Cast
Onslow Stevens as Stanley Stanfield, inventor of the Vanishing Ray and son of the late editor of the Tribune newspaper.
Ada Ince as Gloria Grant, Stanfield’s girlfriend, who is also the estranged daughter of Ward Barnett, having changed her name from the original Gloria Barnett.
James Durkin as Carl Van Dorn, mad scientist ally of Stanfield
Walter Miller as Ward Barnett, villainous businessman
Richard Cramer as Dorgan, Barnett’s spear-point heavy
Edmund Cobb as Kent, one of Barnett’s henchman
Monte Montague as Badger, one of Barnett’s henchman
Al Ferguson as Stroud, one of Barnett’s henchman
Sidney Bracey as Denny, Barnett’s office clerk
J. Frank Glendon as John Cadwell, stockbroker
William Desmond as Editor MacDonald
Beulah Hutton as Sal, a gun moll