Carol Thornton is a character portrayed by Abby Brammell in the ABC crime series Castle. Carol Thornton was the widow of Ike Thornton, late of the 54th Precinct. Ike had been Esposito's partner back in the day, but had come under suspicion from IA of having links to Victor Racine, a crime boss, and had disappeared, apparently eliminated by Racine. When Ike's fingerprint turns up on a dead body it emerges that he faked his death, in order not to be imprisoned on trumped-up charges, and continued his investigation into Racine.