The Fatal Flaw: A Special Edition of 20/20

Killers may think they commit the perfect crime, but the tiny details ultimately stop them from getting away.

After entrepreneur Chris Smith embarks on the trip of a lifetime, his family fears not everything is as it seems – will a fatal flaw unveil a more sinister truth?

When devoted mom Christina Harris dies from a mysterious drug overdose, her family is sure she's been murdered. Could this be the perfect crime, or will one fatal flaw give Christina's family justice?

When Stacey Castor's husband dies of an apparent suicide, not all the pieces add up. Is Stacey a tragic widow or will an overlooked detail reveal that something far more sinister is going on?