Robert, Duke of Normandy, the son of the Duchess Bertha by a fiend who donned the shape of man to prosecute his amour, arrives in Sicily to compete for the hand of the Princess Isabella, which is to be awarded as the prize at a magnificent tournament.  Robert’s daredevil gallantry and extravagance soon earn him the sobriquet of ‘Le Diable,’ and he puts the coping-stone to his folly by gambling away all his possessions at a single sitting, even to his horse and the armour on his back.  Robert has an ame damnee in the shape of a knight named Bertram, to whose malign influence most of his crimes and follies are due.  Bertram is in reality his demon-father, whose every effort is directed to making a thorough-paced villain of his son, so that he may have the pleasure of enjoying his society for all eternity.  In strong contrast to the fiendish malevolence of Bertram stands the gentle figure of Alice, Robert’s foster-sister, who has followed him from Normandy with a message from his dead mother.  Isabella supplies Robert with a fresh horse and arms; nevertheless he is beguiled away from Palermo by some trickery of Bertram’s, and fails to put in an appearance at the tournament.  The only means, therefore, left to him of obtaining the hand of Isabella is to visit the tomb of his mother, and there to pluck a magic branch of cypress, which will enable him to defeat his rivals.  The cypress grows in a deserted convent haunted by the spectres of profligate nuns, and there, amidst infernal orgies, Robert plucks the branch of power.  By its aid he sends the guards of the Princess into a deep sleep, and is only prevented by her passionate entreaties from carrying her off by force.  Yielding to her prayers, he breaks the branch, and his magic power at once deserts him.  He seeks sanctuary from his enemies in the cathedral, and there the last and fiercest strife for the possession of his soul is waged between the powers of good and evil.  On the one hand is Bertram, whose term of power on earth expires at midnight.  He has now discovered himself as Robert’s father, and produces an infernal compact of union which he entreats his son to sign.  On the other is Alice, pleading and affectionate, bearing the last words of Robert’s dead mother, warning him against the fiend who had seduced her.  While Robert is hesitating between the two, midnight strikes, and Bertram sinks with thunder into the pit.  The scene changes, and a glimpse is given of the interior of the cathedral, where the marriage of Robert and Isabella is being celebrated.

‘Robert le Diable’ was an immense success when first produced.  The glitter and tinsel of the story suited Meyerbeer’s showy style, and besides, even when the merely trivial and conventional had been put aside, there remains a fair proportion of the score which has claims to dramatic power.  The triumph of ‘Robert’ militated against the success of ‘Les Huguenots’ (1836), which was at first rather coldly received.  Before long, however, it rivalled the earlier work in popularity, and is now generally looked upon as Meyerbeer’s masterpiece.  The libretto certainly compares favourably with the fatuities of ‘Robert le Diable.’