Olan Soule
— Dr. Clement C. Moore (voice)
Barbara Eiler
— Mrs. Moore (voice)
Hal Smith
— Dr. Sawyer (voice)
Virginia Gregg
— Gretchen (voice)
Laura Turnbull
— (voice)
Shari Turnbull
— (voice)
Douglas Crowther
— (voice)
Diana Lee
— Soloist (voice)
Thurl Ravenscroft
— Soloist (voice)
Bill Cole
— Soloist (voice)
Eleanor Geffert
— Soloist (voice)
Julia Rinker
— Soloist (voice) (as Julie Rinker)