Colton Birchfield is engaged to Jessalyn Thornton.
In 2013, Colton Birchfield and Jessalyn Thornton are planning to marry very soon. Unfortunately, Jessalyn goes missing during her bachelorette party at the old abandoned Thornton Hall on Blackrock Island, a place that is said to be severely haunted by the ghost of Charlotte Thornton.
Colton comes to Blackrock Island along with Jessalyn's mother Clara and Clara's cousin Wade to help search for her. Nancy Drew is called in by paranormal expert Savannah Woodham to investigate the disappearance, and she first meets Colton as she walks up to the front porch of Thornton Hall, where he briefly mistakes her for Jessalyn. Nancy notes that even though he says he's worried about Jessalyn, he doesn't seem as concerned as she would expect the fiance to be. Wade calls him a shifty little punk, and although he's said that about all Jessalyn's boyfriends, he says that with Colton, he means it a little extra. Clara delicately mentions that Colton has had some family troubles in the past, but that it's all been settled now. Jessalyn's friend Addison Hammond doesn't have much of an opinion of him, just that he's always been decent to her.
After overhearing a private phone conversation between him and a girl called Lexie, Nancy corners him into admitting that Lexie is the girl he truly loves and wishes to spend the rest of his life with. He dated her before he got together with Jessalyn and was heartbroken when one day, Lexie dumped him without warning. However, Colton just recently found out that his parents paid Lexie to leave him so that they could then arrange with Clara a marriage between their son and Jessalyn. The Birchfields want access to the Thornton wealth and Clara wants a part of the Birchfields' political influence, so they heavily pushed their children to marry.
The wedding plans have been a large source of stress for Colton ever since they began, not least because Clara makes sure that she is consulted on every single detail of the wedding, from what kind of band will play to where people will sit. In fact, Colton gets so fed up he asks Jessalyn that Clara knows he's not marrying her, right? He dislikes how strict and formal Clara is making the wedding, saying that the event should be fun.
Colton goes on to tell Nancy that happiness has never come easy to him and that he's always felt a little "out of step with the world". Jessalyn is and always has been his best friend, but they never loved each other romantically. When he met Lexie, "everything snapped into place". He is furious that his parents would interfere with such a personal part of his life and declares that he is done looking for their approval. He has come to the island "to try to forget" something. Eventually, he tells Nancy what he forgot: the fact he saw Charlotte the night she died. She had seemed upset about something, but gave him a hug and a piece of paper. Ever since her death, he has been filled with regret, believing that there should have been something that he could have done to help her, even though he was just a child at the time. He gives Nancy the paper that Charlotte gave him: a clue to accessing the safe that contains her will.
If Nancy rescues Jessalyn, Harper, and Clara from the fire at the end of the game, Colton and Jessalyn are both relieved to break off their wedding. As Nancy puts it, "Colton has a lot of things to iron out with his parents and his relationship with Lexie, but he seems determined to do things on his own terms".
- When Jessalyn and Colton first met as children, he thought 'this is the girl that I'm gonna marry'. And then he threw a rock at her face. She still has a little scar that can be seen when she smiles.