Fresh off the heels of her joining Nashville, the actress posted her first photo on set with none other than her O.C. buddy.
The pair worked together until 2004 when Carmack, 36, left The O.C. three years before its finale.
It was announced that Bilson, 35, would be a newcomer on the country music show on March 9 and Carmack was quick to welcome his former costar.
"Can't wait to work with Rachel again... it's been a while!” he wrote on social media. “Welcome to Nashville....... darlin'!"
Kaitlin Doubleday is also joining the CMT show, executive producer and show runner Marshall Herskovitz said in a statement.
"We welcome Rachel and Kaitlin into our incredibly talented ensemble. We fondly anticipate the second half of the season filled with surprising twists and turns that make Nashville so beloved by the fans."
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