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It’s all in the writing concept, the imagery and the music. In essence, the very short, short story, told with a twist that highlights the hook. They’ve left nothing to chance and made every second count. This is your goal, even if your book teaser turns out a little longer, the important thing is that you play up your hook but keep it as short as possible.
Should all book trailers be short teasers like this? Of course not, but the key here is brevity. Be succinct and don't linger. Get to the point as quickly as you can, without giving away too much. Build suspense and curiosity by focusing on your hook, until readers have no choice but to click for the rest.