William Keck of TV Guide has shared some details about what's coming up for Castle in 2013.
There's a two part episode coming up in February during "sweeps" that will introduce Castle's father and suggests it will have a significant effect on Alexis as well as Castle. Castle creator Andrew Marlowe isn't giving away any specifics but joked that Nathan Fillion's fantasy choice for actor to play the role of his on-screen father is Harrison Ford and we couldn't agree more than he would be perfect. However unlikely, Andrew Marlowe does of course have ties to Ford as a result of working with him on his film "Air Force One".... We can dream, right?
In addition to learning something about Castle's mysterious father, Senator Bracken (the man behind Beckett's mother's murder) is expected to make a return appearance and in another episode we learn a bit about Esposito's past.
We shouldn't overlook that Valentine's day is coming up which may just involve a gift exchange between Castle and Beckett in what is set to be a "Real Housewives-type reality show" episode in which actual unscripted-TV stars may appear.
Original source: TVGuide