who is the producer?
Jeff Pinkner .
Fringe (TV series)

Jeff Pinkner was selected to act as the head showrunner and executive producer.
when does peter find out about alternate olivia When she fails to recognize a particular phrase. what is entrada (fringe)? Entrada is an episode of the television series fringe.
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Fringe (TV series) [SEP] Production
Wyman had been a science fiction enthusiast but had worried that he had not written anything in that genre but after learning about the concept of the show, felt his role as an executive producer was "a match made in heaven". Michael Giacchino, Abrams' frequent collaborator, composed the music for the pilot of "Fringe", before handing over duties to his assistants Chad Seiter and Chris Tilton; Tilton took over scoring duties from Season 2 onward. While Giacchino retains an on-screen credit, Abrams himself wrote the series theme music.