Semele was written in 1743, by an already mature Handel, after his opera serias were becoming less well received than they had once been. The big novelty of the time was that Semele was composed entirely in English and is surely the closest that any of his oratorios get towards opera (though today many of them are staged as such). Stage director Barrie Kosky definitely places it in the operatic genre. He creates a very worldly universe in which gods and mortals are prone to the same emotions.