Postcard follows Rebecca, a 21-year-old Nigerian girl on her way to being smuggled into Belgium to work in prostitution. En route, Rebecca witnesses her only friend die. So when she meets her friend's younger sister, Joyce, she decides to take care of her - without telling her the awful truth. While the women endure the hard reality of being prostitutes in Belgium, they also get to see the wealthy lifestyle of their madam Priscilla. During this time, Rebecca shifts from being a 100% victim to becoming a perpetrator herself. Once she has made the decision to become a madam, she realises she must be manipulative to succeed...