This is something special, and of purely specialist interest. Victor Herbert’s 1910 operetta, to a libretto by Rida Johnson Young, was commissioned by Oscar Hammerstein I as a vehicle for the Italian soprano Emma Trentini. Dressed for much of the action en travestie, as a gypsy boy ‘Zingarinello’, she sang the coloratura ‘Italian Street Song’, the romantic ‘I’m falling in love with someone’, and the duet that became one of the most famous American songs of the 20th century, ‘Ah! Sweet mystery of life’.

Naughty Marietta was filmed in 1935, starring Jeanette Macdonald and Nelson Eddy, but apart from the three songs mentioned above and the lusty ‘Tramp, tramp, tramp’ chorus, the film bore little resemblance to the original show.

This 1955 television broadcast, live it must be stressed, is much more faithful and is in its way a monument to the energy and inventiveness of early TV productions. Patrice Munsel in the title-role is high-spirited and quite convincing as the runaway Countess who joins a group of ‘Cascette girls’ – the brides intended for Frenchmen stationed in 1790 New Orleans. When they arrive off the ship, it’s like the end of the journey for the exiles from the finale of Act 3 of Puccini’s Manon Lescaut. In 1943 Munsel had been the youngest soprano engaged by the Metropolitan Opera; she was just 18. By 1955 her Met career was nearly over, but there is nothing here that strains the voice, and she seems a natural for the small screen.

Alfred Drake’s major triumphs in musicals (Oklahoma!, Kiss Me, Kate) were also in the past by this date, but he makes a humorous and agile Dick Warrington, the wholesome American who outwits the corrupt French governor-turned pirate, a fine performance from John Conte. There is some impressive dancing in the extended ballet sequences, and although the production values seem quaint now, this is a fascinating document. Those with a taste for operetta history will be charmed.