Senator Daniel Perrin (portrayed by Alexis Denisof) is a wealthy and powerful US Senator from Virginia who targets the Rossum Corporation (and by extension the Dollhouse) for keeping medical advances secret and conducting illegal human experiments. He is being fed information by some outside party, including information about the Dollhouse.
He mentioned in a press conference that he lost his mother to Alzheimer's before her death. Later, in conversation with his wife Cindy Perrin, he says that Rossum had technology that could have saved his mother.
Thanks to his mysterious benefactor, Perrin acquires information about Madeline Costley's time with the L.A. Dollhouse, which he shares with her, convincing her to come forward and give testimony to the fact the Dollhouse exists. The L.A. Dollhouse staff assume that Cindy is an Active, used to spy on and control Daniel, and think that Madeline is in danger. While Echo is sent to frame Daniel for adultery, Paul attempts to recover Madeline from Cindy.
Daniel suspects that Echo (imprinted as "Bree") is actually a Doll, and takes her to meet with Cindy. They arrive just as Paul uses the Disruptor, which has no effect on Cindy, but briefly disables both Echo and Daniel.
Cindy uses the Disruptor to capture Echo and Daniel, and ships both of them back to Washington DC Dollhouse. Echo (in doll state) and Daniel escape from the Washington house (part of a plan by Bennett Halverson). They remove each other's tracking device, then run to the empty Perrin compound. Daniel was once a drunk and a wastrel. Three years ago, the Washington Dollhouse imprinted him with a modified version of his own personality. This turned him into motivated and crusading politician, all part of a long range plan by Rossum to gain political power.
Bennett remotely imprints Daniel with an assassin program to kill Echo, just as Cindy and other Washington agents arrive. While chasing Echo, Perrin kills a guard and Cindy. Topher shuts down the assassin imprint, causing Daniel to be horrified by what he has done.
Daniel arrives at the Senate hearing, clears Rossum of any wrongdoing and presents evidence that Madeline Costley spent 3 years in a mental institution in Canada, and is still delusional.
Some years later, Perrin eventually becomes president of the United States, and is in office during the start of the Apocalypse. (Epitaphs)