Four years ago, Deborah Voigt was sacked from the lead role in Strauss’s Ariadne auf Naxos at the Royal Opera House because she couldn’t fit into the little black dress she was required to wear. The decision sparked heated debate about whether it mattered what an opera singer looked like. Over the last few years she’s lost 120 pounds and is now back in Covent Garden singing the part she lost. Jenni talks to her about how her career has changed.