Dr Bauerstein

In the novel The Mysterious Affair at Styles, Dr Bauerstein is specialist doctor from London. After a bad nervous breakdown he had come to the village of Styles St. Mary not far from Styles for a rest cure. According to John Cavendish, he is regarded as one of the greatest living experts on poisons. Mary Cavendish also related that Bauerstein had told her that "owing to the general ingnorance of the more uncommon poisons among the medical profession, there were probably countless cases of poisoning quite unsuspected."

Throughout the course of the story, he is also revealed to be a friend of Mary Cavendish. Mary liked it when he visited Styles and would often go out for walks with him. Bauerstein also has a knack of turning up at critical junctures. On the night of the 17th, he turned up at Styles, after having fallen into a pond while trying to collect a specimen of rare fern. Later in the night, he is passing the lodge gates when Baily is driving out to fetch Dr Wilkins. Realising that Emily Inglethorp is in trouble, he makes his way to Styles Court and applies artificial resusitation to her. After Emily dies and Dr Wilkins arrives, he tells Wilkins about his suspicion that Emily died of poisoning, thus setting the direction for the rest of the story.

Bauerstein wears glasses and has a black beard like Alfred Inglethorp.

Agatha Christie's Poirot
Bauerstein is not featured in the 1990 ITV adaptation of The Mysterious Affair at Styles. There, the remark about the ignorance of the more uncommon poisons is still made by Mary Cavendish and is attributed to Dr Wilkins. In the original, Lawrence Cavendish makes a remark that Bauerstein has a bee in his bonnet about poisons and sees them everywhere. Lawrence makes the same remark but this time it applies to Wilkins.