annah sophia stevenson decided to get takeaway from blenheim mcdonald 's for herself and her three-year-old son luca at about 5.20 pm on saturday .
the cosmetic artist , from new zealand , found that after taking three bites of her burger something was not right and then pulled a half eaten , disemboweled cockroach out of her mouth .
ms stevenson said she was trying to work her teeth through what must of been the insect 's shell .