Actors Nathan Fillion and Stana Katic have received widespread popularity from the ABC series Castle. Nathan starred as a novelist Richard Castle and Stana portrayed NYPD Detective Katherine “Kate” Beckett on the series for all the 8 seasons from 2009 to 2016.
Nathan and Stana Katic were speculated to have a relationship in real life as well. The rumors fizzled out when Stana married her long-term boyfriend in 2015.