In a parallel universe of The O.C., Summer Roberts didn't end up with Seth Cohen and Luke Ward didn't move to Portland — they became BFFs and traded in Newport for Nashville. At least, that's what might have happened had they been anything like their real-life counterparts, Rachel Bilson and Chris Carmack. The former costars have found themselves back on TV together again on Nashville, and Bilson celebrated the news with the best Instagram caption. "Welcome to Nashville B****......this is how it's done in Tennessee' @realcarmack #propergreeting #nashvillecmt," she wrote, referencing Luke's iconic "Welcome to The O.C., b*tch," line in the first episode. The only way this could be any more perfect is if Adam Brody and Benjamin McKenzie joined them (unfortunately, they're a little busy changing diapers, we imagine).