Four major characters were played by different actors from those who played them in the pilot Anna Lee: Headcase (1993). These were: Commander Martin Brierly (Michael Bryant in the pilot; John Rowe in the series), Beryl Doyle (Barbara Leigh-Hunt in the pilot; Sonia Graham in the series), Bernie Schiller (Ken Stott in the pilot; Peter Wight in the series) and Stevie Johnson (David Harewood in the pilot; Wil Johnson in the series).