Maybe it’s because yesterday morning, my co-workers kept insisting it was absolutely vital that I watch Sunday’s season finale of “Dexter” as soon as possible. Maybe it’s because I can’t turn off my editor brain while watching TV, so I pick apart the patterns in just about every show I watch. Or maybe it’s because I expected things to go far, far worse than they did. Regardless of the reason, I wasn’t really shocked by the ending that Entertainment Weekly, New York Daily News and the Seattle Post-Intelligencer and plenty of other publications have all called “shocking.”

Right, serious spoilers ahoy.

The turn that shocked so many came in the last few moments of the finale. After returning home from handily dispatching the Trinity Killer, played by John Lithgow, Dexter finds a voice mail message waiting from his wife, Rita, who was on her way to meet Dexter for an impromptu honeymoon. When Dexter tries to call her back, he hears her phone ringing in her purse, which is still next to the counter — and then he finds Rita dead in a bathtub full of blood, with their son, Harrison, sitting in a pool of her blood on the floor.

In spite of everything I already tried to lay the blame on, I think my lack of surprise was mostly because I’m a Joss Whedon fan. Once you’ve watched the entirety of “Buffy: The Vampire Slayer,” “Angel” and “Serenity,” it takes more than the sudden, unexpected and violent death of a major character to surprise you. That’s why I really thought season four of “Dexter” was going to end with the Trinity Killer compressing his kill cycle to take out Dexter’s whole family. Trinity would abduct Cody, kill Astor in the bathtub, force Rita to jump from a building and circle back to try to bludgeon Dexter to death — only to wind up on his kill table instead. By comparison, Rita’s death, which was certainly moving in the way it circled around to Dexter’s own backstory, seemed almost tame.

But Rita’s death — and the huge series of missteps Dexter took in this season — leave big questions about where the show will go from here. Dexter’s relationship with Rita started out as a part of his mask, but as the series developed, she became an anchor for him. What will he do without her? And how in the world will law enforcement officials investigate the disappearance of the Trinity Killer without figuring out that his family knows Dexter Morgan as Kyle Butler? And really, is it possible that Dexter got into and out of a wooden coffin in Trinity’s garage without leaving any evidence behind?

What do you think?