What do you think, Sherlock?

Iranian nuclear scientist goes missing in Saudi Arabia:

CAIRO, Egypt — An award-winning Iranian nuclear scientist traveled to Saudi Arabia earlier this year to perform a religious pilgrimage. He never returned.

Shahram Amiri's mysterious disappearance is turning into a Middle Eastern whodunit involving nuclear secrets and political intrigue, with a new round of accusations emerging this week and the U.S. government still refusing to comment.

There are two big questions: Was Amiri spirited away by Saudi-backed American covert agents? Or did the scientist seize the chance to defect to the West, offering sensitive information in exchange for asylum?

Finger-pointing in Amiri's case has heightened tensions between Iran and Saudi Arabia, which are bitter rivals for regional dominance and self-proclaimed guardians of Islam's two main sects. Iran claimed earlier this week that Saudi Arabia conspired with U.S. agents to abduct Amiri in June and transfer him to the U.S., presumably for interrogations about Iran's controversial nuclear program.