The 'hardest thing' Sam Heughan did to learn his Gaelic accent, according to Outlander's dialect coach.

dhamh Broin, Outlander's dialect coach, revealed the 'hardest thing' Sam Heughan discovered while learning Gaelic for the hit Starz drama.

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Outlander relied heavily on the Gaelic language, which is a crucial component of Scottish history and identity.  

Most of the players, particularly Sam Heughan, had to learn it in order to play their roles as exactly as possible.

Producers engaged the assistance of dialect coach dhamh Broin to ensure that every vowel, accent, and intonation in the hit Starz series was precisely uttered.

The only actor on set who spoke the language was a Sassenach.

Caitriona Balfe, who plays Claire Fraser, the wife of Heughan's Jamie, previously said she was fluent in the ancient language,

but has since lost most of it, saying only "Ciamar a tha thu?" - which translates to "How are you?" in Gaelic.

The actors, including Scottish talents Graham McTavish and Gary Lewis, learned the challenging language during Broin's five-week boot camp.

Broin singled out Heughan for special appreciation, adding the actor was the only one "who could hold it up consistently and dish out the acting while doing it."

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