<P> In a deserted car , Michael discovers the body of the man he planted the GPS tracker on and a badge revealing he was an FBI agent . Sabotaging the air conditioning in the train except for the last car , Michael forces all of the remaining passengers into the last car . He realizes another passenger , a musician , killed the FBI agent ; he also received the same deal for $100,000 , but with instructions to kill Prynne . Michael and the musician fight , at which point the musician is thrown from the train and killed . The real `` Prynne '' is revealed to be a young girl named Sofia , who is holding incriminating information on powerful people and was to go into witness protection at the final stop of the train . Michael asks Sofia why she did not go to the police . She reveals that it was the police who killed Enrique , who was Sofia 's cousin . </P>
<P> In a deserted car , Michael discovers the body of the man he planted the GPS tracker on and a badge revealing he was an FBI agent . Sabotaging the air conditioning in the train except for the last car , Michael forces all of the remaining passengers into the last car . He realizes another passenger , a musician , killed the FBI agent ; he also received the same deal for $100,000 , but with instructions to kill Prynne . Michael and the musician fight , at which point the musician is thrown from the train and killed . The real `` Prynne '' is revealed to be a young girl named Sofia , who is holding incriminating information on powerful people and was to go into witness protection at the final stop of the train . Michael asks Sofia why she did not go to the police . She reveals that it was the police who killed Enrique , who was Sofia 's cousin . </P>
who killed the fbi agent in the commuter
who killed the fbi agent in the commuter
another passenger , a musician
another passenger , a musician