'Castle' season 8 spoilers: Castle and Beckett in danger, LokSat plotting to kill Beckett?

American crime-dramedy series "Castle" season 8 will air its final episode next Monday, and fans will see Castle and Beckett in the middle of a dangerous and tragic situation.
To recap, last week's episode featured Hayley and Alex as they got an unexpected axe-wielding visitor during a blackout. However, the unidentified visitor quickly died from a previous wound. As the team investigated the murder, Castle became so absorbed with the thought that he was marked for death and that the end days may be happening soon.
The official synopsis for next week's milestone episode reads:
With their best lead in hand, Castle and Beckett are ready to take on LokSat. But an unforeseen twist puts their case—and their lives—in jeopardy, on the season finale of "Castle."
As seen in the promo clip, Castle (Nathan Fillion) and Beckett (Stana Katic) will face a situation that puts them in danger. An unidentified man tells Castle about a tragedy bound to happen to his partner, saying, "Kate Beckett is going to be dead by the end of the night and there is nothing you can do about it." The mystery man is likely to be LokSat, but viewers will just have to wait for the finale to know his identity. In the last moments of the sneak peak video, Castle and Beckett are seen hugging, telling each other "I love you."
ABC has yet to announce a renewal for the show, and execs previously announced that they made an alternate ending if the network decides to give them another season. The upcoming finale will also mark Katic's departure from the show. After ABC decided to end her contract, the actress released a press statement which reads:
"Rather than distract from what was an amazing experience I would just like to say that I'm very grateful to ABC for giving me the opportunity to be a part of a much-beloved show. Thank you to the fans,"
Guest stars for next week's episode include Sunkrish Bala to play the role of Vikram Singh, Kristoffer Polaha as Caleb Brown and Jed Rees as Mr. Flynn.
Stay tuned for the finale episode of "Castle" season 8 which airs this coming May 16, Monday at 10 p.m. on ABC.