An action thriller focus on exactly what you’d think: action. Every step the protagonist takes is frought with peril. Obstacles, especially of the physical kind, abound, and create the majority of the suspense in the book.
Maybe a child was kidnapped or a spouse taken. Maybe a murderer needs to be brought to justice. A wrong righted. Whatever crime drives the plot of this thriller, the suspense isn’t usually derived so much from solving the mystery as stopping the next crime.
Like a psychological thriller, the domestic thriller drives suspense from plots of the mind. Internal conflict. Fear. Danger. But what sets a domestic thriller apart is the unique focus on interpersonal relationships.
It’s a thriller… but in the past. But unlike the general genre of historical fiction, suspense is the watchword. (Note: if the thriller is set in the future it’s a sci-fi thriller.)
Lawyers, the system of justice, courts, and their trappings are the central settings of legal thrillers. Themes of right-and-wrong are central, along with suspense that’s often derived in part from the case intruding into the life of the protagonist (often a lawyer).
Life and death is at the heart of the medical thriller, which often takes place primarily in a hospital, doctor’s office, or related setting. And as with a legal thriller, the case at hand often intrudes into the life of the medical worker, upping the stakes.
A military thriller is, defacto, an action thriller. But, more specifically, it’s an action thriller where the main character is a current or former member of the armed forces, usually with a task of monumental proportions that require his/her specialized skills.
As with a crime thriller, an offense has been committed. But with a mystery thriller, much of the suspense is generated as the protagonist tries to figure out what happened. There is some crossover with traditional mysteries here, but in a mystery thriller the main character is in direct jeopardy.
Love a power struggle? A conspiracy? An assassination attempt? Then maybe the political thriller is right for you. This subgenre focuses on the halls of power, plots, international relations, and the figures that inhabit these landscapes.
The psychological thriller is perhaps the biggest subgenre of thriller, and is hallmarked by plots of the mind. Suspense is generated internally. Often the protagonist doesn’t know what is real, or even questions his/her reality. Character, intrigue, emotions, mystery, and inner suspense are defining features of the psychological thriller, rather than physical danger—though there can be plenty of that as well.
Sci-fi thrillers generally take place in the near or distant future, but are still down-to earth compared to sci-fi genres (space opera, terraforming, exploration) that are set in space. Instead, the sci-fi thriller is usually light on the sci-fi and often more speculative in nature. Just enough to provide the suspense.
Spy thrillers as a subgenre evolved out of the twentieth century real-life espionage that was occuring between major powers. Even with spy-against-spy no longer at its Cold War peak, espionage thrillers remain popular, and are often focused on modern intelligence agencies and major threats.
Nearing the territory of the horror genre, a supernatural thriller is a thriller with a spooky, strange, or unsettling vibe. Something’s not right. Maybe a crime defied logical explanation, tension is coming from a paranormal source, or a character has power that defy logic.
Suspense comes when tension—the what might happen of a story—is ratched way up. A thriller becomes a suspense thriller when the focus of the story is not on what is happening but what might happen next.
A technothriller is a research-heavy thriller that relies in part on detailed technology to drive the story. The details—even the minutiae—of the subject matter will be on full display, and often directly affect the storyline.
Thrillers written for a teenage or young adult audience aren’t just obsenity-free thrillers. They’re crafted with the reader in mind; including the age of the protagonist, the emotional backdrop, the types of conflicts, and especially reader experience.