Complex sentence: Benson made his film debut with an uncredited role in "Wait Until Dark" (1967) as the "Boy Tossing Ball" and his Broadway debut in "The Rothschilds" (1970).
Split into simpler sentences: Benson made his film debut with an uncredited role in "Wait Until Dark" (1967) as the "Boy Tossing Ball". He made Broadway debut in "The Rothschilds" (1970).