Mission: Impossible is an American television series, created and initially produced by Bruce Geller, chronicling the exploits of a team of secret government agents known as the Impossible Missions Force (IMF). In the first season the team is led by Dan Briggs, played by Steven Hill; Jim Phelps, played by Peter Graves, takes charge for the remaining seasons. Each episode opens with a fast-paced montage that unfolds as the series' theme music composed by Lalo Schifrin plays, after which in a prologue Briggs or Phelps receives his instructions from a voice delivered on a recording which then self-destructs.