It has been several months since monsters last plagued the town of Stermont, and frankly Alexander Bopp (leader of the Super Secret Monster Patrol) is bored, and misses his friends Rip (immersed in video games) and Nikki (soccer camp), so when his father signs him up for a summer maker program at the library he is happy to go--but soon he starts finding weird old-timey objects, and monster trading cards, and it starts to look like maybe monsters are back in Stermont.

When Alexander Bopp signs up for a summer maker program at the library, he starts finding strange vintage objects and monster trading cards, and begins to believe that monsters have returned to the town of Stermont.