Ian Doyle

Ian Doyle is a mysterious figure from Emily Prentiss's past at Interpol. He is Irish and apparently a very dangerous criminal but what crimes he has commited has never been revealed.

Background
An Irish citizen, Doyle attracted the attention of Interpol who consider him very dangerous. They assigned a team to bring Doyle down. The team was lead by Sean McAllister and comprised of Emily Prentiss, who worked undercover as Lauren Reynolds, Clyde Easter, Tsia Mosley and her boyfriend Jeremy. The team arrested Doyle but he figured out that Prentiss was working undercover to bring him down.

Doyle was imprisonned in a Russian prison for seven years but sweared revenge against those who destroyed his life and took away what he loved most but what it is remains unknown.

Season Six
Prentiss was now working for the FBI when she was contacted by McAllister who told her that Doyle had escaped from prison. He was seen in Russia killing a man and taking his car to get away. Deciding time for his revenge had come, Doyle organized Tsia Mosley's boyfriend's death before levaing for America.

Prentiss called Clyde and Tsia to help her track Doyle down and kill him. Before that could happen, Doyle met with Prentiss and told her that he was there to take her life from her and that she'd better do as he told her to do or he would kill everyone on her team at the FBI.