For Castle (Nathan Fillion) and Beckett (Stana Katic) it was (sort of) back to basics in episode 3 of "Castle" Season 8. With Beckett having blown up their marriage in episode 2 to pursue Senator Bracken's shadow organization and her mother's killer, the pair spent a little more time apart in episode 3, but only a little. After all, there was case to solve and Castle just can not keep away, hoping his sleuth skills would win his wife back in "PhDead." The result was some old school "Castle" fun. 

Castle was not handling the split very well and, while Beckett and Vickram (Sunkrish Bala) made a little headway on her new extra-curricular, vigilante project, Castle was just feeling lonely. In a nod to Spike Jonze's "Her," he even turns to a talking operating system named Lucy for a little companionship. While admittedly funny, Castle without Beckett is a sad sight. 

Watch Castle with Lucy in episode 3 below:

Luckily, a new murder case gave the writer something to do. Castle went undercover as a university professor when the body of Peter, a fraternity student at a local college, turns up brutally murdered, curiously wearing a prison jumpsuit. Castle's disguise helped him and Beckett uncover some dark secrets at the school, including that the Dean was involved in a steamy BDSM relationship with Peter and that a rogue professor had revived the Stanford Prison Experiment (where students role played as guards and prisoners) to conduct psychological tests with her students (hence Peter's jumpsuit). 

The whole thing was a bit contrived, bit it did allow Beckett to show up and bail her estranged husband out of a game of beer pong while undercover at a fraternity party. 

Watch Beckett play beer pong in episode 3 below:

Eventually, Castle and Beckett ended up locking themselves in a cell at the fake prison to try and determine who had broken Peter out and, likely, murdered him. After investigating an air vent, which forced the couple to get close in a moment of palpable romantic tension, the couple realized that only the person in the cell next to Peter could have helped him escape. That would be Amy, the girl who was next in line for a scholarship that, thanks to Peter's inappropriate relationship with the Dean, went to him instead. Case closed, although, Amy claims the prison experiment drove her crazy -- fair point. 

Watch Castle and Beckett share a moment in prison in episode 3 below:

As for Castle and Beckett, though the two saved the day, just like old times, Beckett was not budging on her decision to take space. Castle will have to keep fighting if he wants to win back his wife. 

Watch Beckett decide to stay apart in episode 3 below:


"Castle" airs Mondays at 10 p.m. EDT on ABC.