We've obtained the first images of Kelly playing Gladys in the new BET series, "American Soul" ... which chronicles the rise of "Soul Train" creator and iconic host, Don Cornelius. If you didn't know ... Gladys was one of the first singers booked on the hit show.

As you can see from this scene filmed last week in Atlanta ... the resemblance is uncanny -- Kelly's in 2 outfits for the scene she shot with Sinqua Walls, who's playing Don. The video's great too ... Kelly's on the piano with all eyes fixed on her as she delivers a soulful and breathtaking rendition of "Midnight Train to Georgia."

We caught her out Thursday night and she was all smiles when we brought up the iconic role. Talking about how she studied up for the part, she told us about what it's like to step into such big shoes -- but it sounds like she's not letting the nerves get to her.

It's no wonder Gladys gave her seal of approval back in 2016 when she said on Instagram, "It's no secret that I love my @kellyrowland So many people have said that Kelly would be the perfect person to star in my biopic. What do you think, #Knights?! #stunning #kellyrowland."