Mysterious holes in the ground appear during the night, causing Oliver's bicycle to be destroyed. Who made these holes and why? The child detectives Tiril and Oliver will have to be as smart as Sherlock Holmes to find out.
1935
2022
2021
1958
2020
2016
2024
2015
1992
2010
2006
2012
1994
1991
1996
1988
2017
