For ship officer Larry Ellis to become trained so quickly to impersonate international criminal Steve Challenger is a considerable stretch for the suspension of disbelief that film viewers are expected to swallow. Furthermore, when Ellis is told that his voice doesn't match Challenger's and that he would have to alter it in order to convince all of Challenger's friends and accomplices, Ellis' voice doesn't noticeably change at all. In fact, his voice throughout is somewhat irritating.