Oliver Happ was a Lieutenant Commander in the United States Navy, the husband of Katie Happ and father of Gunner Happ and also the murder victim in the Season 10 episode, Lost at Sea (episode). It was later revealed that Happ was not mentally unstable and had not tried to commit suicide but had actually attempted to stop his colleagues, Petty Officer First Class Josie Sparks and Lieutenant Hank Joplin from selling a helicopter to Shamus Quinn.