Coleman said two years ago she was ready to quit acting, a casualty of one of television's most popular medical dramas. She played Staff Nurse Jude for three years and said it took over her life.

"I did about 90 episodes. Three years of missing people's birthdays and weddings. Also, people would come up to me with their medical problems. They'd say 'I'm using this cream and it's not working'. A lot of people thought I was a nurse. I began to feel like I was working all the time."

After leaving Casualty, Coleman left acting altogether. She spent a year in Africa and started a course in psychology.

She was drawn back by the need to pay some bills, the scripts for Undercover Heart and the chance to wear a new uniform. She researched her role by spending time with a real policeman and said she enjoyed her new look.

"In Undercover Heart I play Sarah May, it's a great part, she's a really strong, straightforward character. Wearing a police belt with a baton, cuffs and CS gas made me feel dead hard!"