Lester Hamilton’s brain was deteriorating due to the tumor, but he wanted to keep working on his research. His wife, however, wanted to preserve his brain before it was ravaged by the cancer so that they could be together in the future. The police find her hubby’s briefcase in her building. She gave it to him as a gift and couldn’t just leave it there after she shot him in a crime of love.
Dr. Ari Weiss is alerted that a client has just flatlined. The signal from a special watch is coming from inside the precinct. Castle and Beckett rush to Cynthia Hamilton’s holding cell. They’re too late. Cynthia swallowed a cyanide pill she had hidden in her ring. Her lifeless hand holds a picture of herself and Lester close to her heart.
Castle wonders if they’ll truly reunite in the future. Beckett believes it’s possible. She says, “That’s what the great love stories are about, right? Beating the odds.” Castle and Beckett both hope they’ll make it. They’re speaking, of course, about Lester and Cynthia. Or are they?