Middle schooler Mary Seaver is prone to energetic outbursts and offbeat behavior, and she’s filled with imaginative ideas. Her teenage sister, Allison, who goes by Al, is her polar opposite and wants nothing more than a typical high school experience filled with sports and school dances. When an alien presence reveals itself to Mary and Al, the girls must put aside their differences to save their town of Pleasant Valley. Al finds herself torn between supporting her younger sister’s mission to protect their friends and family from evil aliens and managing the everyday pressures of teenage life, including complicated friendships, budding romance, and a tough teacher. As if that weren’t enough, the girls must also confront the reemergence of a long-buried secret that could help stop the aliens—but at a potentially life-altering cost. The story blends science-fiction action with coming-of-age themes and high school drama. Mary’s humor and younger sibling perspective provide comic relief that keeps the story from becoming too heavy. The illustrations are engaging and vividly bring the alien characters to life. Mary, Allison, and their family present white, while their friends and teachers represent a racially diverse supporting cast. This is a compelling choice for middle-grade readers who enjoy adventure, family stories, and relatable teen struggles.