Wire-flying is a theatrical stunt

Stunt

A stunt is an unusual and difficult physical feat, or any act requiring a special skill, performed for artistic purposes in TV, theatre, or cinema...

 which involves suspending an actor from high-tension wire

Wire

A wire is a single, usually cylindrical, flexible strand or rod of metal. Wires are used to bear mechanical loads and to carry electricity and telecommunications signals. Wire is commonly formed by drawing the metal through a hole in a die or draw plate. Standard sizes are determined by various...

s, normally with a harness concealed under the costume

Costume

The term costume can refer to wardrobe and dress in general, or to the distinctive style of dress of a particular people, class, or period. Costume may also refer to the artistic arrangement of accessories in a picture, statue, poem, or play, appropriate to the time, place, or other circumstances...

, to simulate the action of flying or falling, especially in the presence of other actors. (When other actors are not in the scene, a visual effect would more often be used to simulate this for reasons of both safety and cost.)

Wire-flying has been done in film, television, and occasionally live theatre for decades. As Superman

Adventures of Superman (TV series)

Adventures of Superman is an American television series based on comic book characters and concepts created in 1938 by Jerry Siegel and Joe Shuster. The show is the first television series to feature Superman and began filming in 1951 in California...

, George Reeves

George Reeves

George Reeves was an American actor best known for his role as Superman in the 1950s television program Adventures of Superman....

was attached to wires for dramatic aerial exits.