Semion Mogilevich, who's believed to be the "boss of bosses" in the Russian mob, is run out of Hungary and back to Russia. He remains powerful and free.

Even after son Vicente and top lieutenant El Chapo are arrested, reputed Sinaloa Cartel chieftain El Mayo is suspected of ruling his region of Mexico.

Suspected of orchestrating the murders of two judges and a series of terror attacks in 1993, Matteo Messina Denaro is still a fugitive at large.

Accused of financing the Rwandan genocide in the '90s, Félicien Kabuga spends decades eluding authorities.

A Muslim convert born in the UK, Samantha Lewthwaite denounces the 7/7 London subway attack. Later, she's suspected of masterminding acts of terror.