This disc’s title inevitably evokes the stop-at-nothing schemer of Handel’s satirical Venetian opera. But as Ann Hallenberg and her musicologist husband Holger Schmitt-Hallenberg point out in their informative notes, there were no fewer than three Agrippinas in the decadent Roman family: the most famous, and least appetising, Julia Agrippina (or Agrippinilla); her mother, virtuous wife of the hero Germanicus; and her mother’s older half-sister, Vipsania Agrippina. Scouring archives in Europe and the US, the Hallenberg duo has assembled an entertaining programme of arias from assorted Baroque operas featuring one or other Agrippina, most recorded for the first time.

With her gleaming high mezzo, evenly produced over a wide range, dazzling agility (no hint of aspirates in the reams of coloratura) and specific sense of character, Ann Hallenberg does this trio of ladies proud. The mingled energy and supple ease of her singing in the first number, a cheerfully bellicose aria from Perti’s Nerone fatto Cesare, sets a template for the whole recital. As the unlovely Julia Agrippina, Hallenberg rants and seethes to thrilling effect in a horn-fuelled bravura aria by Graun. In another ‘rage’ aria by the almost forgotten Giuseppe Orlandini, she achieves the tricky feat of seeming to go berserk in the da capo without coarsening her tone, abetted by percussive, no-holds-barred playing from the ever-lively Il Pomo d’Oro.

In Handel’s ‘Ogni vento’, with its delicious Ländler lilt, Hallenberg exudes a mounting joy at the prospect of making her monster adolescent son Nero emperor. Subtly colouring her tone, she realises each emotional twist and turn of the anguished scena ‘Pensieri, voi mi tormentate’, where Handel manages to elicit a measure of sympathy for his anti-heroine.

As Vipsania Agrippina, Hallenberg rides the waves imperiously in a flamboyant nautical aria by Sammartini, egged on by braying trumpets. In the music for her long-suffering half-sister, she warms and softens her tone, whether in a pair of gentle, touching numbers by Porpora or a poignant aria by Telemann, saturated by bittersweet suspensions. The orchestra is closely miked in the resonant acoustic, occasionally to the detriment of the voice. But this barely detracts from an enterprising recital of fine, largely unknown music, performed with style, flair and tonal beauty by a mezzo unsurpassed in Baroque opera today.