Ricky and Nelly decide to take part in arm wrestling competition during their summer holiday.

Ricky Rapper is a ten year old boy who lives with his aunt Serena and likes to play drums and rap. His aunt breaks her leg, leading to cousin Fanny moving in to take care of the household. Fanny is very strict and that means no more drums for Ricky. With the help of his downstair neighbor Nelly, Ricky seeks to restore the normal order to the apartment.

Ricky Rapper and Nelly Noodlehead leave for the island, where Fanny Rapper works as the resort hostess. At the same time, Uolevi Horsmaniemi arrives with his daughter Wendy, who is little older than Ricky and Nelly. Wendy's arrival confuses the relationship between Ricky and Nelly, as Nelly begins to spend more and more time with Wendy.

Summer vacation has just begun. In honor of it, Serena Rapper and Lennart Lindberg decide to go on holiday. Ricky gets a new bicycle as a consolation, but it disappears mysteriously. Ricky and Nelly Noodlehead go looking for it which turns into a thrilling adventure.

Aunt Fanny and aunt Serena try to find a suitable father figure for Ricky.

Ricky Rapper and Nighthawk Ricky find a buried treasure while digging for worms. Archaeological excavations begin at the site, and when a valuable iron-age ring vanishes, it becomes apparent that there's a site-robbing "nighthawk" at work here.

Serena Rapper gets a strange prediction: a genius has been born to her immediate family. When Serena finds a drawing Ricky has made, she is certain that Ricky is Vincent Van Gogh reborn. She decides to show Ricky's drawing to the intendant of the Art Museum. At the same time, a sketch of one of Van Gogh's paintings is found in Finland! This discovery starts an exciting chain of events, and in the end, the janitor of the Art Museum, a keen amateur detective, helps Ricky and Nelly to solve the mystery.

Ricky Rapper gets a letter from a distant relative who's looking for an heir.

Ricky Rapper is bored because his best friend Nelly Noodlehead is only interested in young pop singer Ville Pyry. Everything changes when downstairs neighbour Lennart Lindberg lends Ricky his old video game.

Nelly spots Ricky on the street and tries to shout at him, but he can't hear her and disappears around the corner. Aunt Serena is surprised to see Ricky in the shop, exploring the candy shelves, when she should be at home vacuuming. Downstairs neighbour Lennart Lindberg asks Ricky to go fishing, but he never shows up. Is there a Ricky look-alike in town? And if so, where and why has he come to the neighborhood?