The son of Sir George Croft of Crofts Limited, a competitor of Birling and Company, he is at the Birling residence to celebrate his recent engagement to Sheila Birling. Gerald is revealed to have known Eva and installed her as his mistress, becoming "the most important person in her life", before ending the relationship. After the revelation of his affair, he is not blamed as heavily as the other characters (Sheila commends him for his honesty and for initially showing Eva compassion, even though he is shown as cowardly and thoughtless for taking advantage of a vulnerable woman). He is caused to confess as soon as he shouts out in shock at hearing the name he had known Eva by (Daisy Renton), allowing the Inspector to investigate Gerald's involvement in Eva's life. Gerald thinks that Goole is not a police inspector, that the family may not all be referring to the same woman and that there may not be a body. Initially he appears to be correct, and does not think the Birlings have anything to feel ashamed of or worry about. He seems excited at the prospect of discovering the 'fake' Inspector and seems almost desperate for others to believe him.
Thus the Inspector’s speech is the ultimate instance in the text of dramatic irony and foreshadowing. For the Inspector predicts that the clash between individual and collective interests will produce need for reckoning throughout Europe and the West. It will have to sort out what belongs to whom, and what people owe to one another. This reckoning, the Inspector says, will not be pleasant or easy. And perhaps it could be avoided altogether if people were more willing to consider those outside their immediate social or family circles. Thus the Inspector is both a hardheaded pragmatist who warns of what can happen to society, and a utopian idealist who wants people to improve because he fundamentally believes that it is possible and right for them to do so. This speech serves as the final word from the Inspector, and he leaves just after. The family, with the exception of Sheila, spends the rest of play not thinking about what the Inspector has said, but wondering about his legitimacy to say it.