Catching Killers

DNA testing was originally used only to determine paternity, until a brutal murder in England changed everything.

Fingerprints have helped authorities save the Mona Lisa, catch the infamous criminal John Dillinger, and in 1892 bring its first killer to justice.

From a sausage factory to the hidden lair of a serial killer, skeletal remains are solving grisly murders and forever changing forensic investigations.

See how maggots, flies, even grasshoppers have become star witnesses in some of the world's most famous murder cases.

The #1 murder weapon of choice for centuries, poison comes in millions of killer compounds. Can modern science ever detect them all?

Grooves inside a gun barrel leave a distinctive mark on bullets, linking bullets to weapons and victims to killers.