Traveling by sea (Situational Irony)
Tom's greatest fear is water, since his parents drowned when he was a child. However, the only way for him to reach Europe, see Dickie, and take a great deal of the Greenleafs' money is by traveling by ship. Later, Tom takes another boat ride, this time because it is his best opportunity to kill Dickie. Again and again, the things Tom wants require him, ironically, to face his greatest fear. Yet he uses his journeys across the water to harm people and cause grief—in spite of the fact that the grief he feels in light of his parents' death caused his fear of water in the first place.
Secrecy (Situational Irony)
When Tom first meets Dickie, he is determined not to reveal the true reason for his visit. Ultimately, though, he gains Dickie's trust by telling him that he was sent by Mr. Greenleaf. In other words, the very topic Tom hopes most to avoid is the one that brings him success. This ironic occurrence is evidence of a difference between Tom and Dickie. While Tom opts for secrecy at every opportunity and is uncomfortable with closeness or bluntness, Dickie appreciates frankness and honesty.
Dickie's views about Tom (Dramatic Irony)
When his relationship with Dickie is first starting to fracture, Tom projects most of his frustration and fear onto Marge. He believes that Marge is stupid for failing to realize that Dickie prefers Tom. This is an instance of dramatic irony, since readers will likely realize well before Tom that this is not the case, and that Dickie will choose Marge's companionship. In this case, Tom does not necessarily lack the evidence he needs to reach a correct conclusion. Instead, wishful thinking and denial create this dramatic irony, since they lead Tom to falsely believe that the situation is evolving in his favor.
Dickie's Disappearance (Situational Irony)
Tom isn't the only character who suffers from illusions about Dickie's inner life. After Dickie is killed, Tom writes Marge forged letters, in which "Dickie" explains that he does not wish to see Marge anymore. Marge, reasonably, assumes that Dickie has disappeared from her life because he does not love her. As a matter of fact, Dickie has not disappeared voluntarily at all—he has been killed precisely because Tom fears that he might like Marge a great deal. This direct contradiction between Marge's belief and the truth of the situation is ironic, and that irony is never quite resolved, since Marge never learns the real reason for Dickie's sudden absence.
The Italian Press (Dramatic Irony)
Tom often scornfully notes the sensationalist tone with which Italian newspapers cover Dickie's disappearance. As a matter of fact, stereotypes about the nature of Italian people and institutions color many of Tom's interactions with them. Ironically, though, the breathless tone of some newspaper coverage hardly compares to the even more sensational reality, which involves murder, unrequited love, disguise, and mistaken identity. Tom imagines that drama and exaggeration are foreign traits, unaware of the fact that he has created far more drama than the press could hope to convey.
