A minor matter to be sure, however, the degree certificate visible on Magnus' desk during the opening credits does appear to be incorrect. It describes Magnus as an alumnus of Oxford University; whereas, as a woman, she is an alumna. Also, a doctorate of medicine at Oxford is described by the initials DM, not MD. Finally, slightly obscured by her glasses, are the words "Class of 1921". At Oxford, students are grouped by their year of matriculation (the year they enter the university), not the year they complete their degree. Until recently, the concept of a graduating "class" was an entirely foreign concept in England - and remains such at Oxford.