beloved engineer Scotty, played by James Doohan, was doing far more behind the scenes than fans ever realised - including playing secret roles no one recognised. While Doohan is best known for shouting about warp engines and declaring what the ship "cannae take it," he was also quietly lending his voice to multiple minor characters across the series. Thanks to his experience as a voice actor and his distinctive thick Scottish accent as Scotty, he was the perfect choice to double up - and it seems hardly anyone noticed.

As detailed by the fan site Accidentally Correct Writing, Doohan "provided the voices for several minor characters who appeared only as audio communications or recordings." Because the voices weren't on screen - and because his normal accent was so strong - audiences didn't twig that it was the same actor. And that wasn't the only time a familiar face (or voice) was used in a sneaky second role.

William Shatner, who played Captain Kirk, also portrayed several versions of himself across different episodes - from an android double to a body-swap victim.

In episodes like The Enemy Within, Whom Gods Destroy, and Turnabout Intruder, Shatner pulled double duty, showcasing his versatility as the captain and his twisted counterparts.

Elsewhere in the Star Trek universe, this kind of multi-tasking wasn't unusual. Actor Malachi Throne, who voiced the Talosian Keeper in the unaired pilot The Cage, returned later as Commodore Mendez in The Menagerie.

Because the show recycled footage from The Cage, Throne's voice for The Keeper had to be electronically altered so viewers wouldn't clock it was him again. This kind of casting trickery was a clever behind-the-scenes solution to the series' famously tight budget.

But it also speaks to the unsung talent of its cast - particularly Doohan, whose engineering degree in real life once helped creator Gene Roddenberry out of a dangerous boating situation. His contribution to the franchise didn't go unnoticed by those who worked with him.

William Shatner, speaking in later years while filming his documentary The Captains, admitted accoring to tvtropes: "Unfortunately, it was too late to apologise to James Doohan or DeForest Kelley, but I did get a chance to apologise to Leonard before he died. The magnanimous son-of-a-b***h forgave me,"

Despite the legacy of catchphrases wrongly attributed to him - from "She's gonna blow!" to "Ah doon have th' pow'r, Cap'n!" - the real James Doohan left his mark in more ways than one. Doohan passed away in 2005, but his legacy lives on - not just in Star Trek lore, but even in outer space.

In 2008, a portion of his ashes were secretly smuggled aboard the International Space Station, fulfilling his lifelong dream of reaching the stars, just like the character he made iconic.

His son, Chris Doohan, has honored his father's memory by portraying Scotty in fan productions and making cameo appearances in recent Star Trek films.