From my interview with Richard Gordon that was published a while back in VW:

"Then when we did Corridors Of Blood, MGM, who had then come in and taken world distribution, said 'Well, we need another picture to go with that also.' And the idea was to make First Man Into Space which again had Marshall Thompson in it, who was the lead in Fiend Without A Face. So we did those two pictures and then of course Sputnik came along, and MGM said 'There's no point in holding First Man Into Space until Corridors Of Blood is ready. Let's go with First Man Into Space and sell it by itself.' So they put it out as a single feature - this would have been around 1958, '59 - and it did extremely well."
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