Something is not right in Bayport. After a series of unfortunate (yet harmless) pranks, it looks like Frank and Joe have caught their suspect surprisingly early. Their classmate, Seth Diller, has taken his love of filmmaking a bit too far. But shortly after Frank and Joe confront Seth, there are fresh outbreaks of Seth-like pranks. Except these aren't as harmless. After a bit of investigating, the Hardy Boys uncover evidence of the Red Arrow - a group that will stop at nothing to bring chaos and crime to Bayport's peaceful existence.

Frank and Joe Hardy have been invited to take part in a conservation mission by a marine biologist at the Bayport Aquarium. The boys get to go on an all-expenses-paid trip to the lush and beautiful Florida Keys to help save sharks! But the trip’s purpose is suddenly sidelined when a paddle boarder goes missing, and rumors start that the disappearance is the result of a shark attack. After spending so much time learning about the local shark population, the Hardy Boys aren’t buying the story.

Dear Diary...Bess, George, and I are actually in Alaska! Everywhere you look, there are massive mountains and sparkling, deep-blue waters. We're on the maiden voyage of the Arctic Star luxury cruise ship, and my old friend, Becca Wright, the assistant cruise director, needs our help. She received threatening emails before even setting sail; then a bloody body turned up in the swimming pool.

Jack Phillips's allergy to sunshine confines him to the shadows, leaving him lonely, and at risk of life-threatening burns every time he steps into the light. Shadow jumping on the rooftops at dusk, makes him feel alive. And free. But Jack's condition is suddenly worse than ever, and only his missing scientist dad can save him. As Jack and his new friend, Beth, begin their frantic search and delve into his dad's past for clues, they have no idea what they are about to uncover.

There was something else out on the sea by the rocks - something dark that seemed to lurch out of the waves...What could it be? Julian, Dick and Anne are spending the holidays with their tomboy cousin George and her dog, Timothy. One day, George takes them to explore nearby Kirrin Island, with its rocky little coast and old ruined castle on the top. Over on the island, they make a thrilling discovery, which leads them deep into the dungeons of Kirrin Castle on a dangerous adventure. Who - and what - will they find there?