Upon his return home he decided he wanted to pursue a singing career and began opera studies with first his mother and then Jean Lassalle in Paris.
He reached La Scala in Milan in 1911 where he sang in the Italian premières of Richard Strauss's Der Rosenkavalier (as Ochs) and Engelbert Humperdinck's Königskinder (as the Fiddler).
Other roles he appeared in at La Scala included Bluebeard in Ariane et Barbe-bleue, Falstaff in Otto Nicolai's The Merry Wives of Windsor, Geronimo in Domenico Cimarosa's Il matrimonio segreto, and both Pagner and Hans Sachs in Die Meistersinger von Nürnberg.
[1] In the years before World War II, Ludikar performed at the opera houses in Rome, Trieste, Turin, Paris, Budapest and Havana.
In 1913-1914 he worked with the Boston Opera Company, having a great success there as Archibaldo in Italo Montemezzi's L'amore dei tre re and in the role of Hans Sachs.
He sang in several more United States premieres with the company including Puccini's La Rondine (March 10, 1928, Rambaldo), Ildebrando Pizzetti's Fra Gherardo (March 21, 1929, Guido), Giuseppe Verdi's Luisa Miller (December 21, 1929, Wurm), Nikolai Rimsky-Korsakov's Sadko (January 25, 1930, the Sea King), and Felice Lattuada's Le Preziose Ridicole (December 10, 1930, Gorgibus).
His repertoire there included Alvise in La Gioconda, Archibaldo, Capulet in Roméo et Juliette, Ashby in La Fanciulla del West, Colline in La Bohème, Daland in The Flying Dutchman, Don Alfonso in Così Fan Tutte, Ferrando in Il trovatore, Geronte in Manon Lescaut, Gesler in William Tell, Golaud in Pelléas et Mélisande, Hermann in Tannhäuser, Hunding in Die Walküre, Leporello, Kecal in The Bartered Bride, King Heinrich in Lohengrin, King Marke, Mathieu in Andrea Chénier, Pedro in L'Africaine, Peter in Hänsel und Gretel, Pogner, Ramfis in Aida, Rocco in Fidelio, Sarastro, Simone in Gianni Schicchi, and Sparafucile in Rigoletto.
Political developments shortly before signature of the Munich Agreement coupled with financial problems led to the theatre's closing in September 1938, effectively ending Ludikar's opera career.
[1] After the end of World War II, Ludikar wanted to move to Austria but was forbidden to leave by the now Soviet controlled government in his country.