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.
1984
1971
2022
1937
2018
1983
2014
2010
1931
2015
2023
2006
1962
2021
2012
1969
1985
