1. At the end when the hit man was about to commit suicide he gives the detective a riddle to find the tape. At that point why didn't he just tell the detective straight out where the tape was hidden?
2. ...and far less important, why do they say the occasional sentence in english?
1. Ledda knew that the two Police agencies didn't get along. If you look in the background, you see a Constable there (not part of Vincke's agency). Ledda was clever enough to know that the Constabulary was on the payroll of the corrupt politicians and that they would bury the tape if they got to it before Vincke. Ledda gave up the tape's location in a riddle that only Vincke would understand.
2. The movie was in several languages. If you're multi lingual, like me, and you go to Europe, you'll hear slip in and out of different laguages all day long.
The OPs first question seems valid. The only people in the car was Ledda and the two detectives. No one else could hear them.
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