Well, 'The Da Vinci Code' by Dan Brown can be considered in this category. It has a thrilling mystery centered around art and history, and there's a bit of a romantic sub - plot. 'And Then There Were None' by Agatha Christie also fits. Although it's more of a pure mystery, there are elements of relationships and unspoken romances among the characters stranded on the island. 'The Time Traveler's Wife' by Audrey Niffenegger is a beautiful and unique love story with a touch of mystery as the main character time - travels and his wife has to deal with his sudden disappearances and reappearances.
I think 'The Girl on the Train' by Paula Hawkins is a top choice. It's about a woman who witnesses something strange while commuting, and there's also a love triangle and lots of secrets. 'Big Little Lies' by Liane Moriarty is also excellent. It has multiple storylines that blend mystery and romance, dealing with the lives of several women in a community and a mysterious death. Then there's 'The Kiss Quotient' by Helen Hoang, which is a unique romance mystery where the main character, who has Asperger's, hires an escort and they end up in a real relationship while solving some personal mysteries.
Chapter 98, "Golden Sore Powder", is the clearest early answer because it turns Frost Wolf's situation into a concrete plot event. The setup is The specific effects of the Medicine Decoction Pot were unclear to..., but the pressure keeps building through A month ago, Xia Hong personally approached him and instructed him to....
Chapter 142, "%, The Boiling Brought by the Martial Arts Training Ground 【8000 Major Chapter Appeal for Subscription】", is the clearest early answer because it turns Great Xia's situation into a concrete plot event. The chapter gives readers a real answer by opening on Everyone was holding their breath, waiting for him to break through. and ending on When the light dissipated, the ground had turned black and was.... In story terms, the chapter closes with Heavy consumption;
Chapter 57, "Solidified Fire Oil is Used Up", is the clearest early answer because it turns Wood Puppet Monster's situation into a concrete plot event. The chapter gives readers a real answer by opening on When the solidified fire oil was taken out of the iron refining... and ending on Luo Ming caught it, quickly breaking it into four pieces, handing one....
Chapter 55, "It's Just Playing with Wood", is the clearest early answer because it turns Xia Hong's situation into a concrete plot event. The setup is Leader Luo, please restrain your grief., but the pressure keeps building through The most urgent thing now is to see if anyone is still alive..
Chapter 80, "Outsmarting the Frost Wolf Pack", is the clearest early answer because it turns Xia Hong's situation into a concrete plot event. A useful checkpoint is the way the scene starts with How did we end up encountering a pack of Bone Spur Frost Wolves? and follows through with Xia Hong and Luo Ming turned their heads, their faces instantly....
Chapter 106, "Expand the Hunting Grounds, Camp Expansion [3-in-1]", is the clearest early answer because it turns Shi Qing's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Xia Hong maintained a calm expression and nodded. and follows through with If not for Xia Chuan having the Wood Puppet Black Blade, leaving him....
Chapter 123, "Arrow Bamboo Forest, Rat King, New Camp", is the clearest early answer because the buildup finally cashes out in a real clash. Early on, Facing such an overwhelming victory, Xia Hong couldn't help but feel.... By the end, Not to mention, it shot out directly from underground!. Inside the broader battle storyline, the chapter closes with At this moment, Xia Chuan had placed the unconscious Luo Yuan on the ground.
Chapter 159, "Blood and Flesh Wall, The Leader Hasn't Broken Through Yet?", is the clearest early answer because it turns Demon Sheep's situation into a concrete plot event. Early on, The hundred-meter-thick wooden walls, arranged in a slanted cross.... By the end, In an instant, a dozen Cold Beasts were floundering at the wooden....
Chapter 56, "Intermediate?", is the clearest early answer because it turns Intermediate's situation into a concrete plot event. The setup is The hardness of the Golden Frost Tree, Xia Hong had experienced it..., but the pressure keeps building through Though harder than the Red Frost Tree, under the immense strength....
Chapter 103, "The 2nd Earth-digging Realm", is the clearest early answer because Luo Ming finally turns buildup into a real advancement. It opens with In the valley mine, an iron ore the size of a palm was chiseled from... and closes on Xia Hong followed the opened path into the crowd, seeing Luo Yuan....