Book Adrenaline is a book discovery service that helps readers find free and discounted mystery and thriller ebooks. Since 2016, its team has searched thousands of titles each month, selecting bestselling authors, award winners, highly rated books, and hidden gems across genres such as crime, suspense, legal mysteries, psychological thrillers, and conspiracy fiction. Members receive one daily email featuring limited-time offers, with many books free and discounts of up to 90%. Signing up is free, and readers can unsubscribe at any time.

The ebooks are available through retailers including Amazon, Apple Books, Barnes & Noble, and Kobo, and can be read on Kindle devices, phones, tablets, computers, and other major e-readers. No Kindle Unlimited or other subscription is required, and purchased books are yours to keep. Book Adrenaline says it does not sell members’ email addresses and aims to send only its daily deals email. In addition to helping readers discover books, the brand offers authors and publishers opportunities to submit free-book promotions and purchase featured placements.