From Wikipedia:
See How They Run is a 1964 chase film broadcast on NBC. It is generally regarded as the first movie made for television.
Plot:
Three orphans head for the US, unknowingly carrying important evidence pointing to the existence of a corrupt international cartel, which has just murdered their father. The cartel is desperate to retrieve the evidence.
Cast:
John Forsythe as Martin Young
Senta Berger as Orlando Miller
Jane Wyatt as Augusta Flanders
Pamela Franklin as Tirza Green
Franchot Tone as Baron Frood
Leslie Nielsen as Elliott Green
George Kennedy as Rudy
Jami Fields as Maggie Green
Jackie Jones as Jamsey Green
Harlan Warde as Manley