L'Éclair (The Lightning Flash) is an opéra comique in 3 acts by Fromental Halévy to a libretto by Jules-Henri Vernoy de Saint-Georges.

L'Éclair was premiered by the Paris Opéra-Comique at the Salle de la Bourse on 16 December 1835; Jacques Offenbach was a cellist in the orchestra.

It was first performed in the United States on 16 February 1837 at the Théâtre d'Orléans in New Orleans.

[1] It remained popular in the 19th century (Emma Calvé sang in it in 1885) and has been revived in modern times.

It recounts the amours of the Englishman George and the American Lyonel for two sisters, Henriette and the widow Mme.