"The Scarlet Lake Mystery: A Rick Brant Science-Adventure Story" by Harold L. Goodwin is a fiction novel written in the late 20th century. It follows the adventures of a young protagonist, Rick Brant, and his friends as they embark on a thrilling mission involving rocket launches and an enigmatic enemy known as the "Earthman." The book combines elements of science and adventure as the characters navigate challenges related to their work at a secretive rocket base and uncover a mystery that threatens their projects. The opening of the novel introduces Rick and his friends, Scotty and Barby, on Spindrift Island as they practice using a sling while waiting for Dr. Gordon, who has arrived from a rocket experimental station. Rick learns about a special assignment involving a secret government project at a rocket base, where sabotage has been occurring. Dr. Gordon explains the mysterious connection to someone referred to as the "Earthman" after a rocket launch that went awry. The trio is eager to participate and work undercover at the Scarlet Lake base to uncover the identity of the saboteur, setting the stage for an exciting and dangerous adventure filled with high-tech intrigue and personal growth. (This is an automatically generated summary.)