Joseph Conrad's novel The Secret Agent is a story of espionage, deceit, and Conrad's truth about society. The story takes a primary focus on Mr. Verloc, the secret agent, and the narrator spends very much of the novel focusing on his character and agenda. Winnie, his wife, as well as his brother-in-law, Stevie, lie in the background, so much so that in normal circumstances, Verloc will be chatting with his friends while Stevie and Winnie take to a separate room.
The relationship between Stevie and Winnie is very complex and important, as readers will discover as they reach the final chapters of the book. Stevie becomes such a likable character to all of us, and we feel a deeper connection with him if not from the beginning, than as the story progresses, than we have ever felt with Verloc. Winnie also becomes a shock to most of us, and we may be appalled at this other side of her personality she reveals when she becomes a person of rage and ferocity and kills her husband, but can't we all imagine being as devastated and furious as Winnie (but take it out in a more legal and socially acceptable way)? The reason that we as humans can connect so strongly to characters can happen in many ways, including a strong connection we feel to a character, personally, or we experience an event or happening that we are passionate about, and that is what fuels most of my feelings on The Secret Agent.
I believe that Conrad set out writing The Secret Agent to make a statement on what he thought of society. Stevie is the personification of innocence and purity in the story. He was tricked by Verloc, his most trusted role model, to transport a bomb. Not only was he putting Stevie in the exact danger that killed him, he was involving this immaculate human in his own malicious and nefarious plot. Stevie was a victim of senseless violence.
For Conrad to write a character like Stevie, he is indirectly telling the story of the other virtuous victims who had their lives taken from them by the acts of terrorism. Stevie is written to be the true hero of this story, as the only character to not commit any crime, and to stay pure in the midst of evil.