"I saw things I can't unsee." Last night on The Voice we saw one of the most emotional performances of the season.

Last night, The Voice delivered one of the most emotional performances of the season.

Crissy Ashcroft, 49, took to the stage in her military uniform. Visibly nervous, she stood in darkness with her eyes closed.

Ashcroft performed Cold Chisel’s ‘When the war is over’, keeping her eyes firmly shut for most of the song. Midway through, Delta Goodrem turned her chair. It wasn’t until Ashcroft hit her final note that she discovered she had progressed to the next round. She was unable to contain her excitement.

What the judges didn’t know was why that song was significant to Ashcroft. Fighting back tears, she revealed that during her deployment to Afghanistan she “saw things I can’t unsee, and they’ll be with me forever”.

During her 13 year stationing, Ashcroft was severely injured. She explained to the judges that she bears “physical and mental scars,” and suffers from PTSD.

Like many PTSD sufferers, Ashcroft’s trauma is triggered by loud noises. In an interview backstage she said “If I see a car backfire, I’ll just hit the deck, which looks kind of strange in the middle of Sydney.”

Ashcroft is the sixth contestant to join team Delta.