With a few of our favorite The 100 characters trapped outside the bunker, we knew Wednesday's season finale was going to be a terrifying race against the death wave, but we didn't know it would be this intense!

In this exclusive sneak peek of the action-packed episode, Raven (Lindsey Morgan) runs down every single way things could go wrong, each resulting in certain death. In 90 minutes, Raven, Bellamy (Bob Morley), Clarke (Eliza Taylor) & Co. have to run a six-hour pre-flight check, retrieve the oxygen generator, and turn a cockpit for two into a cockpit for eight (not to mention, load it up with enough food to keep them alive).

Oh, but if you thought that must be all, you're sorely mistaken. As Raven explains, the CO2 scrubbers on the rocket won't support all eight of them, and their oxygen tanks only hold an hour of air. That means they'll only have one hour to get into orbit, land in the Ring's hangar bay and fire up the life support system.

Never one to get derailed by pessimism, Bellamy steps up to help lead the team into action after Raven's terrible, but wholly necessary, version of a pep talk. "Now we know the many ways we might die today, why don't you tell us what we have to do to live?"

The 100 finale airs Wednesdays at 9/8c on the CW.

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