One of the few vehicles on Langeoog - population 2,100 - is the local ambulance, which was stolen on the night of the 13th of February.
An unknown thief had lifted the keys for the vehicle and taken it for a short joyride before abandoning it.
But the culprit hadn't reckoned with the sharp-eyed island constabulary, who spotted evidence inside the car linking whoever 'borrowed' it to the theft of an iPhone in January.
Since they already had a suspect in that case, they had their colleagues in Esens, the closest town on the mainland, stop and search the 18-year-old - apparently far from a seasoned thief, as he turned out to have both the stolen iPhone and the missing ambulance keys on him.
Overcome with remorse - or possibly overawed by this display of detective work - the young man immediately confessed and offered to pay compensation for his crimes.
Since he was driving illegally as well as stealing, though, he will face an investigation for driving without a license.
"Even on Langeoog, you need a license" police said on Thursday.