Possible Clues:

• Why the manoeuvre to capture it boomeranged?
• Reason to put it back in transport
• Why it's back in touch
• Reason it was put back in turn
• Whodunit necessity
• The reason why
• Reason it came back in turn
• Reason for doing something, perhaps a crime
• Reason for acting
• Detective is always looking for it in strange movie about last commandment