To add to that, throughout the play but mainly toward the end of the play the Inspector abuses his power over the Birlings insulting them and ‘taking the mickey’ whenever he gets the chance. What's more is that right the way through the play the audience knows more than the characters do, this is something called dramatic irony.
The Inspector describes Eva’s death very freely. This is when he states, “A woman died in the infirmary. She had been taken there this afternoon because she had swallowed a lot of strong disinfectant. Burned her inside out of course”. The way the inspector questions the family is also very unusual. He already knows the answers to the questions he is about to ask. Whenever a family member has another surprise he is never shocked or even startled. He never takes notes, he is alone and the fact that he only ever shows the photograph of Eva/Daisy to one person at a time. This is all evidence that would imply that the Inspector is not an actual police inspector. This again builds up tension.
The photograph is used to create tension because you are never surely know that the photo he is showing one family member is the same as the one he shows another. This could mean nothing or everything. So the photo Mr Birling sees is of a girl he recognises and has sacked, but the photo Eric sees may not be the same woman who he got pregnant. They might be completely different people and none of them might have died in the first place. Priestley was again building up tension.
Also, the Inspector in himself creates tension through the way he acts towards the Birlings and Gerald. He always seems to necessitate being in control. He is constantly interrupting them all and making sure that they think he is superior, even though the Birlings believe that they are bigger, so to speak. The Inspector is generally mysterious in his temperament, which adds to the tension. Priestley gave the Inspector a suitable name to match his personality – “Goole” which sounds like ‘ghoul’, which is another word for ghost.
The Inspector’s mysterious character is vital in the structure of the novel. Priestley created a source of tension far greater than I have ever seen by producing the Inspector’s ignorance and yet, he still seems rather superior to the upper class Birlings. Then the writer leaves us on a cliff-hanger/mystery by saying that the Inspector doesn’t actually exist. Was he real? If he was, who was he? If not, what was he?
