Improvisation in Theater was already being developed in the early years of the 20th century and has continued in regular theatrical technique with increasing interest after the mid-century mark. It has also been used in many ways in cinema production, directors like Altman made major use of Improv. even to the point at times of not furnishing actors with a script. Full stage and film improvisation can bring life to a production in surprisingly interesting ways, and in the last quarter century improvisation has been widely used. Often unrecognized if aptly done, it can fuse invisibly into the fabric of a written stage script or film scenario. There are hundreds of groups worldwide which one way or another feature the idea of improvisational theater in plays and theater workshops.
Improvisation as an important part of Theater, uses a variety of experimental techniques designed to enliven the performance of a dramatic reading or a performed staged play. Without formally realizing it, stage directors have tried to incorporate an actor’s intuitions into performed parts of a play. When confronted with a stiff and unconvincing part, a director will often say to ad-lib it a bit, and if the actor has a good improvisational skill, he will act out the part on his own as if he were the writer laying out the script. Life and liveliness come naturally from Improvisation and in theater and cinema this has been established as a common and worthwhile technique. We often can’t be sure when a part is being improvised or read from memorized script, except by noting that it sounds very agile and good, perhaps better than the surrounding scripted material. Reversing the situation, a skilled actor can perform a part brilliantly by reading it from script as if he were improvising the words, of which there are well known examples in the history of modern cinema.