After finally settling into a peaceful co-parenting routine with her ex-husband Ryle, Lily's world is turned upside down when she unexpectedly crosses paths with her first love, Atlas. The years apart haven't dimmed their connection, and when Atlas asks her out, she dares to hope that timing might finally be on their side.

But embracing a second chance at love is never simple. Ryle is still a constant presence in her life—and the one man he can't stand being near his ex-wife and daughter is Atlas Corrigan. As old emotions rekindle, tensions rise, and Lily finds herself torn between a past she thought she'd left behind and a future she desperately wants.

Switching between Lily and Atlas's perspectives, It Starts with Us delves into the depths of their histories and the challenges that threaten to keep them apart. Can they overcome the obstacles of their intertwined pasts, or will the lingering shadows of jealousy and regret destroy their hope for a new beginning?

Their story began years ago, but this is where they must decide how it ends.