Giove in Argo, a concert performance of Handel's 1739 pasticcio opera, was perhaps the most historically significant event at this year's Göttingen festival; happily, it was also an artistically enjoyable performance. It was preceded by an informative English language talk by John Roberts, the scholar who identified the missing arias which allowed the work to be, at last, performed.

Known also by its English title Jupiter in Argo, the work was composed - or perhaps one should say put together - by Handel in the dying years of the popularity of his Italian operas in London, and as he was beginning to concentrate on English oratorios. It comprises arias from many of his earlier operas (Teseo, Scipione, Alcina, Arminio, Berenice, Ezio, Faramondo, Imeneo) and the less classifiable works Parnasso in festa, Il pastor fido and Acis and Galatea. As well as a string of da capo/dal segno arias, there are eight coros, two of them repeated. There is therefore grounds to consider whether Giove should not also be classified as an oratorio, or perhaps a serenata. It is not clear whether it was staged, semi-staged, or sung as an oratorio; it was described by Handel himself as an opera. Apparently composed in haste to take advantage of two Italian singers newly arrived in London, Costanza Posterla and her inexperienced daughter, the work played to a full house in the King's Theatre on the first night but failed to please the audience, and after one more performance, disappeared from the stage. Doyen of Handel scholars Winton Dean suggested it was possible to reconstruct, but wondered whether it would be worth doing "except as a curiosity."

Since the original performances, the work fell into even deeper disregard than Handel's other operas. An autograph score of only Act I is known, and a libretto; there was the matter of missing arias and no recitatives for Acts II and III. Roberts discovered the missing two arias in the Fitzwilliam Museum, when it turned out that they were in fact by Handel's younger contemporary Francesco Araia; they were probably "suitcase arias" provided by Signora Posterla. He has himself produced a performance score which includes the Araia arias, and composed replacements for the missing recitative. This will be published in the Hallische Haendel-Ausgabe, and, as well as Göttingen, will be performed at the Halle festival this month.

Giove in Argo uses a libretto by Luccini, previously set as an opera in 1717 by Lotti, and derives from the lighter side of Greek mythology. Roberts describes it as a Pastoral piece, and the action takes place in the woods, with more or less everyone disguised as shepherds/shepherdesses. The story concerns the amorous adventures of Giove and his pursuit of not one but two young women, Calisto and Iside. Iside (or Isis) is destined for Erasto (or Osiris), and Calisto is under the patronage of Diana who of course insists on her chastity. There are further complications due to the backstory in which Calisto's father Licaone killed Iside's father Inachus. As was never the case in Greek mythology both ladies end up with virtue intact courtesy a benevolent Giove. Instead of Calisto being turned into a bear, in the last act a bear appears out of nowhere to menace Iside and be killed by Erasto. The complexity (and indeed silliness) of the stories in baroque operas has never been a bar to their popularity with those who appreciate the music and can embrace their conventions.

At Göttingen, Giove in Argo was performed under the musical direction of Alan Curtis and his estimable band, IL Complesso Barocco. It was performed in concert, but the commitment and interaction of the soloists generally led to a dramatically lively experience. The singers were all relatively young performers, but far from the inexperience of Signorina Posterla. Italian soprano Laura Cherici turned in a remarkable performance as Calisto. Not only did she deploy a voice of considerable beauty and great flexibility in her bravura arias, she threw her whole body into the performance. In Act II, the well known Tornami a vagheggiar from Alcina - such an attractive aria for a soprano that it was famously purloined by Joan Sutherland's Alcina from its rightful character Morgana - was a whirlwind of ornamentation and bodily commitment, but that was as nothing to the Act III Combattuta da più venti (from Faramondo), where her voice was volcanic and her body provided an on-stage earthquake.

Mezzo-soprano Mary-Ellen Nesi was far more physically stately as Iside, but her dramatic commitment was just as evident. Her Questa d'un fido amore (one of the Araia arias) was just as vocally dynamic as Combattuta, showing off her rich burnished tone and smooth coloratura. Theodora Baka was Diana, initially showing good phrasing in a clear soprano, but she seemed somewhat strained by Act III. Arete was sung by tenor Zachary Stains in serviceable fashion, with appropriately dashing demeanor. His voice did not blend terribly well with that of Cherici in their duet (Vado e vivo, from Faramondo and also Imeneo). Vito Priante was Erasto, in good voice if a little wayward in intonation, and Vittorio Prato took the other bass role as Licaone; his strong, confident and very expressive singing made one wish he had more than one aria.

In 1739, it seems Handel had available the same choral forces used in Saul and Israel in Egypt. For this revival, the soloists sang the coros, augmented by four extra voices. They were placed behind the orchestra, which was seated on the stage, with the soloists coming round to the front for their arias. This arrangement did lead to some drowning out of the choral parts. The orchestra played in lively fashion, although the horns were particularly wayward at the very beginning.

Was it worth doing as more than a mere curiosity? As performed here, and noting that it was a concert performance, it was certainly a lively entertainment, and the story appeared to have just as much coherence as many. One way in which it differed from the more familiar operas was in the juxtaposition of one bravura aria after another, especially in Act III, providing a level of brilliance - particularly as sung by this cast - not often encountered. There seems no reason why this work should not take its place in what is becoming the standard Handelian operatic repertoire.