Plot hole: Could Howie have not telephoned for more officers? When Howie first walks into Summerisle you can see poles that are used to carry telephone lines. Later on you see outside The Post Office (May Morrison's shop) a box that is used an exchange box for telephone lines in the town. The story gives us the belief that there were no telephones on Summerisle, which is why Howie was unable to send for help. But there is clear evidence of a telephone network on the island. Even if the islanders somehow manage to prevent him making a call, what about the radio on the plane?
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Suggested correction: Howie checks the radio on the plane. It had been sabotaged and wouldn't turn on. This was shown in that very scene.
