A #FriendstoLovers STEM rom-com, The Best Friend Experiment is the fifth book in the Chemistry Lessons series, originally published as Experimental Marine Biology. Each book in the series features a brand-new couple with their own HEA and can be read in any order. "Just friends" is all that Brooke and Dylan have ever been. Except for that one night in high school, but they don't talk about that... Growing up, Dylan was the one guy Brooke could always trust. No longer the kids they once were, she's a successful marine biologist working toward her PhD in California, and he's a hot-shot underwear model in New York. But now Dylan is in town for a few days, crashing on Brooke's couch and repaying the favour by acting as her date to a friend's wedding. Soon the pair can't untangle the fake flirting from what's real, and their friendship gains some heart-racing benefits. And it's all going great...until it isn't. Dylan is going back to New York at the end of the week, and Brooke may have accidentally broken his heart. Could this be the end of their friendship or the beginning of something much more?