In "Contract Baby," Lynne Graham captivates readers with a blend of melodrama and romance that epitomizes the quintessential modern love story tangled in contractual bindings. The book is a part of Graham’s prolific writing career in the romance genre, especially within the Harlequin Mills & Boon territory. It tells the story of Polly, a young woman who finds herself entwined in a relationship strictly guided by a business agreement, but as often happens in Graham's novels, the heart knows no bounds of contract.

At the core of this narrative is Polly Dawson, who is presented not just as a damsel in distress, but a character with depth and resilience. Polly’s predicament starts when her sister’s well-being hangs on a thread. Desperate to find a solution, Polly finds herself agreeing to an audacious contract offered by the rich and commanding Rashad, a businessman that Polly knows too little about. Rashad proposes that Polly marry him and bear his child in exchange for the financial help she desperately needs. What follows is a richly spun tale of tangled emotions and unforeseen entanglements.

Rashad is the archetype of a Lynne Graham hero: enigmatic, wealthy, and with a back story that perfectly shapes his aloofness. His motivations for wanting a contract marriage are not out of a lack of belief in love but a desire to control his emotional investments with precision. This is where Graham’s strength as a romance writer shines, crafting characters that uphold traditional traits yet bust them with their emotional layers and complexities.

The narrative moves quickly, propelled by Graham's skilful pacing, ensuring readers are continually engaged. Each chapter builds upon the tension and chemistry between Polly and Rashad, integrating subplots that enrich the central story rather than distract. The dialogue is crisp, often laden with emotive undertones, pushing the characters' relational dynamics to the forefront of reader's minds. It is this unwavering focus on the evolving relationship that forms the book's crux, making it irresistible for lovers of contemporary romance.

Graham does not shy away from embedding societal themes within her story. Issues of economic disparity and the burdens of societal expectations are woven in, providing a backdrop that adds realism and relatability. Readers witness not only a contractual relationship but are also offered a lens into how personal values and societal pressures shape romantic relationships.

The emotional quotient of "Contract Baby" peaks as Polly and Rashad traverse through predictable milestones, but with unpredictable emotional reverberations. Polly, initially viewing the arrangement as a dire necessity, gradually sees the layers beneath Rashad’s business-like exterior. Conversely, Rashad, who maintains a controlled facade, finds in Polly a spontaneity that challenges his structured world. Here, Graham masterfully portrays the evolution of emotions and how they can lead to genuine connections regardless of the formal start.

However, what stands out in “Contract Baby” is how Graham manages to turn a commonplace trope into a refreshing narrative, leaving the reader invested in the protagonists’ path to self-discovery and mutual understanding. The chemistry between the characters sizzles subtly, avoiding overt sensationalism but instead remaining palpable and realistic.

The novel also brings to the fore the supporting characters who are not mere placeholders but add layers to the main story. Whether it is Polly's sister, whose welfare is paramount to Polly’s decisions, or Rashad’s close associates who provide insights into his true character, each supporting role is well fleshed out, making the world of "Contract Baby" multidimensional.

Beautifully encapsulated, the book concludes with a satisfying resolution that adheres to the romance genre’s requisite happy ending but feels earned and true to the characters’ journey. It is a testimony to Graham’s skill that the conclusion does not come off as contrived but a natural culmination of the characters' growth and shared experiences.

In summary, "Contract Baby" by Lynne Graham offers more than a simple romance. It delves into themes of societal norms, personal growth, and the unexpected beauty found in contractual relationships turned profound. Graham's narrative prowess ensures a gripping read, fulfilling the fantasies of those who cherish romance while offering substance that reflects on personal and societal dimensions. Hence, this book is a commendable addition to the romance genre, promising and delivering to both avid followers of Graham and new readers looking for a story with both heart and depth.