Isaac and Thea were once close, but they've grown apart. Thea works tirelessly, convinced she can prove everyone around her wrong - convinced she can prove that time travel is possible. But when one of her attempts goes wrong, she finds herself picking up the phone and calling her old friend. Isaac is in New York - it's the middle of the night, but when he sees who's calling him, he cannot ignore his phone. At Thea's request, he travels home, determined to help her in her hour of need. But neither of them are prepared for what they will discover when he gets there.