Ironhaven

The Earth is dying, and Lucian Hoyt is going to die with it thanks to his parents cancelling his pass aboard the last shuttle off the planet. There is hope, though–a brilliant inventor has come up with a plan to build a ship to evacuate those who've been left behind.

That inventor turns out to be Genevieve Scott, Lucian's bitter ex-fiancée. If they're going to work together to get off the planet, they need to put their past aside, but even melting the ice between them can't erase all the scars.