The mystery of Howe's disappearance and murder continued for nearly ten years until the investigation had a major break.

The mystery of her disappearance has excited speculation ever since.

It used the mystery of the first expedition's disappearance to lure us here.

Only The Shadow knew the mystery of his own disappearance.

But deep down he was a little relieved that the mystery of his father's disappearance had finally been solved.

The mystery of his disappearance was not revealed until late last night.

I can't say that these developments solve the mystery of Ethan's disappearance.

But this doesn't begin to solve the mystery of his disappearance.

But that still didn't clear up the mystery of her disappearance.

We found a note from Ambrose waiting for us which increased rather than explained the mystery of his disappearance.