In the second half of Season Five, Anson Fullerton (Ep. 512), the co-creator of the organization that Michael worked so hard to destroy, uses evidence that ties Fiona to the bombing of a British consulate to blackmail Michael into doing his bidding.
Looking for a way out from under Anson's thumb, Jesse and Sam recruit Madeline to pose as a witness to the consulate bombing. If she can gain access to the detective's computer, she can download all his information pertaining to the investigation and find out how strong a case the police have against Fiona. Only problem is, Madeline barely knows how to turn a computer on, much less remove and download the information stored on a computer's memory-chip.
Meanwhile, Anson orders Michael to go to Puerto Rico to obtain a computer virus that will erase any evidence linking Anson to the organization that burned Michael from the CIA's database. But all Michael finds is a cowardly hacker who's been hiding out from a deadly international drug dealer. Michael has to protect the squirrely hacker and steal the well-guarded virus because, if Michael doesn't do exactly what Anson asks, Fiona will be sent to prison for the rest of her life.