"The bat" is an eco-detective story for teenagers. The events of this long story are based on Marta's diary, where she writes about her younger brother Sylvester's adventures in their country house during their summer holidays. Excitement is never lacking . From chasing down a graffiti artist, to trying to capture the mysterious outlaw Bat, the two siblings stay true to their inner call to protect nature and the people they love. The main heroes behave in a way that defies the norms of society. They are not afraud to look silly, if it means protecting their "littlest brothers" - the animals. At times they resort to some rather drastic measures in their attempts to reduce pollution and rescue nature. Nonetheless, the author is on the side of these 'eco-warriors' since their motives are always disarmingly genuine and noble.