When the king of the gods falls head over heels in love with you, seriously bad stuff happens. If you're a Handelian soprano like Semele, however, it happens very tunefully and in a thoroughly pleasant, elegant and cheerful manner for the whole evening.

If you're confused as to the difference between opera and oratorio, Semele is the perfect aid to your confusion. The work has virtually every feature of a baroque Italian opera - a light-hearted love-based plot rather than a worthy biblical one, music that moves the story along and is well suited to staging, a broad cast of characters with the usual operatic balance of voices, etc. Except that it was written to an English libretto by William Congreve, and Handel attempted to disguise it as an oratorio for Lent, presumably because it meant he could get paid. Unsurprisingly, the more religious concertgoers were unimpressed by a tale with such loose morals, and Semele tanked, to languish unheard for nearly 200 years.

Which is a pity, since it's a lot of fun and a great piece of music. It's one of Handel's last operas, and the style is definitely developing: the "da capo" arias which are so damaging to dramatic flow are thin on the ground, the action moves briskly, and there are plenty of good tunes to keep you engaged. There are also a very large number of full-tilt Handel semiquavers to keep the singers on their toes.

All this makes Semele quite a challenging number for a tiny low-budget opera company like Hampstead Garden Opera, but they clearly rose to the challenge with gusto. The production deserves to win prizes in some form of alternative opera awards ceremony: "most creative use of bubble-wrap" for costume designer Rachel Szmukler, "best coloratura performance while being pelted with pillows" for Zachary Devin as Jupiter, "best ability to keep a straight face while wearing a nightie" for Martin Musgrave and Ed Bonner and "best ability to stay still under dust sheets" for too many of the cast to list individually. The production frames the first act as a typical squabbling family - the news from Mount Olympus comes through the ageing TV around which they are clustered - and brings it off entertainingly.

Oliver-John Ruthven's ensemble "Musica Poetica" kept up a blistering pace for the whole evening (there are very few slow interludes). A fair bit of playing inaccuracy got rather exposed in the orchestral-only passages, but they were fine when accompanying the voices, and their constantly upbeat brilliance and dynamism meant you had to forgive them. As usual, HGO assembled a fine cast of up-and-coming singers. Robyn Parton negotiated the fearsome technical difficulties of the title role with apparent ease, giving us a pretty timbre and plenty of flibbertigibbet characterisation along the way, Zachary Devin gave us a powerful Jupiter, and Bartholomew Lawrence showed a lovely rich voice as the sleep god Somnus. The other main roles were all sung creditably, although there were some struggles to keep the power level through the longer low-register passages.

The chorus were top of the class: the large ensemble numbers came through with much enthusiasm and fine balance. All in all, Semele is brisk and light on the ear, and HGO presented a cheerful, bubbly performance.