Jarrett is a character who makes a one-time appearance in the Season 2 episode titled "Inn at the End of the Road".
Jarrett is an executive at the Sandex Corporation, a technology firm which has developed "Loki", a top-secret flight computer working on bio-feedback mechanisms which is capable of extracting the best performance out of any aircraft, thereby transforming even old obsolete aircraft into potent fighters. However, Archangel tells Hawke and Dominic, "Jarrett is an idiot and a showboat." He can't resist showing off "Loki" to his board of directors and ends up losing the device when a terrorist gang led by Steele mount a daring raid on the board meeting.
Jarrett's position in the corporation is not mentioned in the episode. He could be the CEO, president of the board or some other executive. The name of his corporation is not mentioned either but the camera does have a brief shot of the corporate logo in the board room.