Najee is the true main antagonist of Captain Phillips. He is based on one of the Somali pirates who hijacked the Maersk Alabama in 2009.
In the beginning, Abduwali Muse picked him because he wanted someone strong, despite the protests of other pirates since Najee was from another village. Najee may be strong, but he is also reckless, impatient, and quick to lose his temper. Eventually, Najee overtakes the role of main antagonist from Muse as while Muse continuously insists on keeping Phillips alive (because of both their need to keep their hostage and his growing affection for Phillips), Najee believes Phillips a liability and constantly tries to kill him.
In the climax of the film, he is quick to know that the NAVY was trying to pretend about the elders. When he catches Captain Richard Phillips writing a farewell letter to his family, he tries to take it away before Phillips attacks him only to be restrained and beaten. Najee orders the rest of the pirates (sans Muse who was taken into custody) to tie him up and blindfold him. He ignored the other two pirates' pleas not to kill him (as they have begun to realize the futility of their situation and begin to believe the best option is to surrender) and repeatedly points out the NAVY was lying about the elders. As he aims the gun at Phillips, the commanding officer of the USS Bainbridge, Frank Castellano, asks the crew to stop towing the lifeboat. It causes the lifeboat to tip slowly causing Najee almost lose his balance but giving the SEAL snipers have clear shots on all three pirates. At that moment, Castellano shouts, "Execute!", and the snipers opened fire, killing Najee and the other two pirates, saving Captain Phillips' life.