A Fire at the Big Unveiling (Situational Irony)
At the big event at his factory when Preston Tucker is finally supposed to unveil the prototype of his automobile not just to his investors, but to the entire world, he stages a big spectacle. The irony comes with the fact that the car was just slapped together for the event and is barely operating in time for its time in the spotlight. Just when Tucker is about to bring the car out, it starts spilling oil and creates a small fire. He must put out a PR fire by keeping the audience entertained while his crew puts out a literal fire backstage.
"Don't get to close to people. You'll catch their dreams." (Verbal irony)
Abe Karatz tells Preston about something his mother used to say to him. He thought she was saying "Don't get too close to people. You'll catch their dreams," but really she used to say, "You'll catch their germs." It simultaneously explains Abe's cold demeanor and shows us just how infectious Tucker really was. No one around him could help but catch his dreams.
Who's running the company? (Dramatic irony)
We know well before Preston Tucker that in order for his company to attract investors, no one is going to let him be in charge. The fact that we know and he doesn't creates one of the most significant tensions in the plot, making his ultimate confrontation with the appointed chairman all the more satisfying.
The Confidence Trick (Situational irony)
The greatest irony of the film comes when Tucker is charged with defrauding investors for a scheme that was initially displayed in the movie as an indication of his gumption. He sent Abe to car dealerships to invest in an automobile which didn't exist yet. What seemed ingenious at the time actually proved to be a move that made him an untrustworthy businessman, especially when the car repeatedly failed to materialize.
