Amphitheatre seats are available for £18 and stalls seats for £40.
The offer is valid for performances on 27 and 29 September at 6.30pm and 3 October at 3pm.
Book online using this link or call the Royal Opera House on 020 7304 4000 quoting the code TZOO Niobe Offer.
My advice? Hold on long enough and they might just have to give them away.