Stacey Newman was a temporary person at HQP. She was friends with Tanya and was left somewhat shaken after Ianto Jones arrived at HQP with a beeping device. She began to question what exactly it was that HQP did.
When Tanya pulled out a gun to kill Ianto and Yvonne Hartman, Stacey fled with them, but ran away to what she believed was her home after they told her that she was a temporary person. Ianto followed her and told her that her family and friends were not real, which she sadly accepted. She agreed to help and tricked WOTAN.
Stacey died outside of HQP with Ianto, having reached the end of her short life at 5pm. (AUDIO: 9 to 5)