h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

That strange accent he used in Star Trek, sounding as if the Dick Van Dyke School of Hollywood Cockney had set up a special class to do Scottish accents (it's since added a Daphne Moon Lecture Theatre to do what Americans fondly beleive to be a Manchester accent)isn't entirely his fault or down to his being cloth-eared.

Doohan spent time in Scotland with the RCAF, after all. This came in handy when atttending auditions for a Scottish chief engineer in space: he read the part in broad and impeccable Aberdonian, got the part, but was told to change it to make it more accessible to American TV viewers. So he tried Glaswegian (on Americans?), then a softer Highland voice, and was vetoed every time: work with a studio-approved language coach created the almost-but-not-quite Scottish accent deemed ideal for the part.

So the accent he used really wasn't his fault, and if he'd had his way, Scotty would have been an Aberdeen man with an accent that would have earned a nodding "Aye, that an better will do" from the Granite City.