Mona, a migrant domestic worker is employed by London housewife, Theodora. At first Theodora only asks Mona to clean and occasionally cook for her, but as unwanted pressures from a demanding elderly mother and a lazy, unemployed son begin to take their toll, Theodora deflects these onto Mona. Slowly, imperceptibly, Theodora's demands increase until she is treating her as nothing better than a slave.
Mona is trapped. She needs to send money back to her daughter to pay for her education and then Theodora takes her passport from her. Controlling Mona becomes Theodora's goal, and Mona is going to have to take extreme measures of her own to escape the control of her increasingly abusive employer.
So when a murder is committed, who is to blame? Is it Theodora at the end of her tether, or Mona, desperate to find a way out?