He rubbed elbows with the Hungarian literati of the day including the playwright Ferenc Molnár, whose most famous work Liliom is known to English-speaking audiences as the Rodgers and Hammerstein musical Carousel.

It only made sense then that Niki was encouraged to put pen to paper and as a young adult began to produce his own little one-scene plays for the various small theatres and cabarets around the city.

It came then as a great satisfaction that his first three-act play, A "legboldogabb" ember, The Happiest Man, a play about an embittered factory worker and the dream world to which he escapes for solace, won him the prestigious Hungarian Royal Academy Award for Literature in 1934, the Hungarian equivalent of the American Pulitzer Prize – quite an achievement for a man barely into his 30s.

But fame in the insular Hungarian language-speaking community of Yorkville, Manhattan, New York is not the same as making it as a playwright to a larger English-speaking American audience.

In the fall of 1939 he married Florence Herman, an aspiring young actress and the daughter of a successful local entrepreneur, a Cunard Line travel agent, landlord and financial exchange merchant.

On December 28th, 1944, he completed the transition and became a fully naturalized American citizen and officially adopted the single name now most frequently referenced, Miklós László.

The play was adapted as a movie script by Samson Raphaelson and became the Ernst Lubitsch motion picture The Shop Around the Corner (1940),[6] starring James Stewart, Frank Morgan, and Margaret Sullavan.

This production was a faithful adaptation of the MGM movie script The Shop Around the Corner and ran for the 2002 season in Paris at the Théâtre Montparnasse winning top honors.

In June 2004 Parfumerie was produced for the first time as an English-language play by the theater department of the University of Illinois, after James Berton Harris, the director of the department's Summerfest, found a translation of the original script in papers donated by Samson Raphaelson to the university's Rare Book and Special Collections Library.

[7][8] A new adaptation of the play by E. P. Dowdall, a nephew of Miklós László, premiered in December 2009 as The Perfume Shop at the Asolo Repertory Theatre in Sarasota, Florida.

[10] In the early 1940s he also wrote a screenplay Katherine which was picked up by MGM and became the motion picture The Big City (1948) starring Margaret O'Brien, Robert Preston, Danny Thomas and George Murphy.

Entitled St. Lazar's Pharmacy it is the story of a man learning the lessons of the true value of “home” as compared to the many lures of a false and deceiving world of empty promises.