Ah! Curse your sudden but inevitable betrayal, Lexa.

'The 100' Season 2: What Is The City Of Light? Jason Rothenberg Teases Shocking Answer

The 100 kicked off its two-part finale on Wednesday, leaving fans staring in disbelief as the Grounder/Sky People alliance came crashing down in epic style. It seems Lexa has discovered the ultimate way to end a budding relationship - just drop your girlfriend and her war like a 97-year-old grenade.

Cage Wallace (Johnny Whitworth) floundered as Clarke (Eliza Taylor) and Lexa (Alycia Debnam Carey) came knocking at his fortress door during "Blood Must Have blood: Part 1," and the cowardly usurper turned tail and ran to daddy before the episode was through. The president's panic opened up a more diplomatic approach for the Grounders, allowing Lexa and her imprisoned tribesmen to walk out of Mount Weather without saving any of the imprisoned Arkers.

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The sudden turn of event's left Clarke looking like someone sucker-punched her in the stomach, but series creator Jason Rothenberg doesn't think Lexa's betrayal came as any real surprise.

"She let the missile fall on TonDC so that she could win the war. The deal offered by Cage was that win," Rothenberg explained. "She ended the Reaping and made peace with their greatest enemy. All it cost her was the Sky People."

So, what's the next step in Clarke's battle against Mount Weather? "Blood Must have Blood: Part 2" will see Bellamy (Bob Morley) and co. continue to break out of the Mountain Men's stronghold while Clarke finds help in unexpected places. As always, expect the bodies to stack up like cordwood before season's end.

Find out more when The 100 airs Wednesdays at 9 p.m. ET on The CW. Click the video below to see a preview for the second part of the season 2 finale.