Jephtha, New Theatre, Cardiff

The Rev Thomas Morell of Buckland, Hertfordshire, did us all a favour with Jephtha. One of Handel's most charged Old Testament oratorios, with its reek of Euripides in its story of a father faced with sacrificing his child that heralds Idomeneo and Gluck's Iphigenia, Jephtha plumps for a Dryden resolution but spares us none of the horror along the way.

Staging of Handel oratorios - more sophisticated texts than Handel's preceding operas - will always spark doubts. But with Katie Mitchell's new staging for Welsh National Opera, such fears scarcely arise. Mitchell has the gift of controlling without intruding; as her recent WNO Katya Kabanova showed (with the same splendid designer, Vicki Mortimer), her work is a real case of "art which conceals art". The text is enhanced; there are no finicky diversions; and the words speak clear.

This staging boasts a cast to die for. Chris Purves is an operatic baritone of weight and charisma (his range includes Gluck. Here, he exudes the bullishness of Ariel Sharon bracing for a cabinet meeting, and sets the nerves tingling with Zebul's prescient "It must be so". Things never looked back. Susan Bickley as the distraught mother with terrifying dreams moves superbly and pierces the soul; fresh from her ENO Cassandra, her Storge is up to the gills in tragic desolation. When she hurtles up Mortimer's amazing cantilever staircase - intelligently employed by Mitchell in this 1940s production, Bickley encapsulates this whole sorry Old Testament mess.

Director and designer frame scenes cleverly: the quasi-photographic effect (used in Katya) of a telescoping black frontdrop to mask natty swift scene changes; shrewd use of upstage facing; and cunningly plotted blockings, especially for the women. Mitchell serves her emotionally crowded hero, Mark Padmore (not a natural actor, but learning fast), superbly, moving him notches beyond his recent St John Passion for Deborah Warner and placing him to advantage in key da capo arias. The variety with which they together encompass Jephtha's growing isolation is a triumph; the accuracy of Padmore's coloratura, with Paul McCreesh's players in perfect attendance, is breathtaking.

Handel's magnificent choruses fit the glorious WNO chorus like a glove. From the outset, McCreesh had the WNO oboes and bassoons sounding like period players; one late lovers' duet, and the girl's fluted solo, were exquisite. Special laurels to the two young leads: vocally, to Daniel Taylor, utterly faultless as the hapless Hamor; visually, to Sarah Tynan as Iphis, who, abetted by red-white imagery and Mitchell's almost Oedipodean central peripateia, brings to Jephtha's ravaged child a pathos worthy of Titus Andronicus: a thrilling effort, and an exciting debut.

Tomorrow and 4 June (029-2087 8889), then touring