The Modern Theatre opened on June 25, 1914, with owner Jacob Lourie (1874-1940) at the helm. The first film shown was The Only Son, featuring Thomas W. Ross.
Lourie was a genial man with a keen business sense, and his marketing ideas would reverberate from Boston to Hollywood.
When others were calling the marriage of sound and film a gimmick, Lourie decided to invest in new technology that would be the end to silent films. He installed the Vitaphone system, which synchronized music and sound effects with the motion picture.
A 1927 ad proclaimed: 
Extraordinary Announcement!
Beginning Sat., May 21 – First Permanent Boston Installation at Popular Prices of
THE REVOLUTIONARY SENSATION IN CINEMA EXPOSITION!
First Vitaphone Program John Barrymore in “Don Juan”
Soon thereafter came the release of the first “talkie,” and once again Lourie was the first in Boston to show the groundbreaking movie. The Jazz Singer took the innovation of the Vitaphone one step further, using it to incorporate spoken dialogue into the film.
With the advent of talking pictures, the movie industry moved into the mainstream of American entertainment. The decline of vaudeville houses in the vicinity of the Modern soon followed.

When other theaters began showing films in an effort to stay competitive, Lourie continued to adapt by showing two films for the price of one.
With the invention of the double feature came the need for a larger volume of films, and Hollywood studios complied by creating a slew
of low-budget movies. These B movies also engaged up-and-coming directors and provided work for actors on the way up the ladder to stardom.
Lourie built a theater empire as owner of New England Theatres Operating Company, or NETOCO, which at its height operated 35 theaters. He paired the Modern Theatre with the Beacon, and the two movie houses showed the same films, with the reels being transported from one venue to the other by streetcar between showings.