There are times when artist's are at the "top of their game". A period of time where they are, as athletes say, in the zone.

By 1978 Loretta Lynn was already a country music superstar. With over a decade of smash hits, she was among the top stars in music. Her song "Coal Miner's Daughter" had become her signature song and remains so today.

And then the movie of the same name came out and Loretta became known to millions more. People who had no particular interest in country music fell in love with this lady.

In this vintage video clip from the Merv Griffin Show in November, 1978, Loretta sings her signature classic, then sits down for a chat.

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