Thriller openings are usually either discrete, stylised, narrative or credits over blank screen. Discrete openings are separated sequence which stand apart from the film. Stylised openings are edited greatly. Credits over a blank screen start with a black screen before slowly introducing images. Narrative openings introduce the story rather than focus on credits.
An example of a narrative opening would be the film "The Shining". This is as the film starts with introducing the storyline rather than focusing on credits.
An example of a discrete would be the film "Enemy of the state". This is a discrete film opening as it stands apart from the film and has been specifically edited to be an "opening". It does not specifically lead to the film such which would be found in narrative openings.
An example of a credits with a black screen would be the beginning of the start of the film "Memento". The start of the opening begins with plain text over a black screen.
An example of a stylised opening would be "Mesrine - Killer Instinct". This opening is heavily edited in post-production.