Steve Marriott, who played Harry Smith's son Jack, was later to become the lead singer and guitarist with influential English rock group, the Small Faces.
The voiceover at the beginning is Peter Sellers. He also provided one of the voices heard on a television sequence.
At one point when Rev. Smallwood (Peter Sellers) is preaching from the pulpit, a young boy is seen in the foreground reading a copy of Vladimir Nabokov's "Lolita". Sellers played Quilty in Stanley Kubrick's film version of that book.
According to film historian Robert Osborne, Peter Sellers' portrayal of Rev. Smallwood was based on (and is a "dead-on" impression of) one of his teachers - Brother Cornelius - in a Catholic school.
The rocket launch, supposedly from a remote British island base, used footage of an actual NASA Mercury capsule launch from Cape Canaveral in Florida.