Brat i sestra, Miron i Melita, odlaze na zimovanje prijatelju Zoltanu (Liptusu) u Kopačevo. Po dolasku, iste noći, dječak Halasz nađen je promrzao na obali gdje bunca da ga je napao bijeli duh na jednom od otoka u močvari. Baba Etelka otkrije tajnu kako je duh viđen još davno i kako ne može s otoka pa se sveti svakome tko stupi na njega. Lovci pokrenu istragu, ali ni oni ni liječnici ne mogu pomoći Halaszu. Zato Miron, Liptus i Melita odluče naći duha i ponuditi mu da ga čamcem prebace na obalu u zamjenu da ozdravi njihovog prijatelja...

After Liptus arrives in a small village from the city, he calls his best friends, Miron and Melita, on winter holidays in Kopacevo. That same night, while they are all sleeping cozily, from their deep sleep Miron and Melita are woken by the disturbing sounds of villagers, carrying flares and disappearing into the darkness at the end of the street. At the docks, they find Halasz, a boy known for his bravery. He is cold, pale from shock, and babbling a white ghost. While most of the villagers don't believe Halasz's story, older citizens recall a long time ago when a forgotten spirit would scare people at night in dark and foggy swamps. Everyone locks themselves in their houses and Halasz ends up in a hospital where the doctors can't help him. Miron, Liptus, and Melita, now alone, take matters into their own hands, revealing the secret of the ghost and saving their friend.