Riley Lorrent doesn't do feelings. As a 26-year-old cognitive psychologist, she deals in data, patterns and proof. People, on the other hand, are unpredictable entities she'd rather avoid.

So, when she's invited to discuss her work on morning show television, Riley expects a polite, controlled conversation.

Instead, she gets Declan Montgomery.

A fitness influencer and personal trainer, Declan is infuriatingly confident and far too accustomed to being right. When their on-air clash spirals into something sharper, he proposes a challenge: design a six-month experiment to see whose approach works best. Mind versus body, science versus instinct.

Riley should walk away. Instead, she agrees.

Now forced into close quarters with a man she can't stand, Riley is pushed beyond controlled variables and neat conclusions. Because this experiment isn't just testing theories. It's testing her limits, her patterns and everything she thought she understood about herself.

Declan thinks he can figure her out. Riley knows that's impossible.

After all, she's never done an experiment in love... let alone been in one.