Castle (2009-present)

He's a crime novelist, she's the NYPD homicide detective he tailed for inspiration. We've known they were meant for each other since season 1, but it wasn't until the season 3 finale, when Beckett took a bullet, that Castle admitted his feelings. Of course, she pretended she hadn't heard him say ''I love you,'' and when he found out she had, he pulled away again. But (SPOILER ALERT!!) in the season 4 finale, he repeated the words as he tried to explain why he was desperate for her to let her mother's murder go — she could be killed if she doesn't. Beckett continued investigating without him, and... well, just read our recap and what creator Andrew Marlowe had to say about the episode's ending.