Peter Saxon - Through the Dark Curtain

Published by Lancer (73-714) in 1968. Peter Saxon was originally a pseudonym of W. Howard Baker but it became a house name when Baker took over the editorial reins of the Sexton Blake line. At least five other authors published as Peter Saxon - Wilfred McNeilly, Martin Thomas, Rex Dolphin, Stephen D. Frances and Ross Richards - this particular novel was by Richards. Cover art is not credited.