著名建筑设计师沈皓死在他亲手设计的顶级隔音书房“回音室”里，现场门窗反锁、完美得像一起意外。刑警张振国与许晴逐一审问当天出入过公寓的人，要从一间不可能的密室里找出真相。
本段之前： 保安顾伯、生意伙伴林慧芳相继接受询问后，轮到了死者年轻的助理周毅。这一段里，神情紧张的周毅坚称自己当天只在门口放下文件、从未进屋，并反复表白对老师沈皓的崇敬。
告老还乡的前朝首辅沈从安，眼看独子沈徽——如今的吏部侍郎——被卷入圣上新政的清查田亩之案，担心儿子锋芒太露、成为他人棋子。一家人在表面的平静下，各怀心事。
本段之前： 暮色中的相府书房，沈从安与老妻陆氏谈起近日归家总带倦意的儿子沈徽。老人借“潮水有涨有落”道出忧虑、暗示该寻一处避风的港湾；话音刚落，管事秦嬷嬷便在帘外回报大爷归家，沈徽迈步进了书房。
大雾笼罩的江城，画家顾远山失踪两天。刑警队长陆振宇顺着妻子、学生、邻居的证词层层推进，慢慢接近一个关于“雾”与告别的真相。
本段之前： 接到报案后，陆振宇与年轻警员周子昂赶到画家公寓。这一段是他们刚进门的开场：周子昂简报案情，刚出差归来、神情反常镇定的画家妻子林蕙迎入二人，陆振宇开始询问顾远山最后的行踪。
老人赵桂兰摔了一跤，引爆了女儿一家积压已久的养老矛盾。卖掉老房、送进养老院的“最优方案”，与一份无法用金钱衡量的亲情，在餐桌上正面相撞。
本段之前： 女儿林慧萍把刚出院的母亲接到自己家。压抑的晚饭桌上，这一段是谈判的开场：外孙张远航只顾玩手机惹老人不快，而林慧萍小心翼翼地把“以后养老”的话题引了出来。
辞了职、独自西行的苏晚，在开往乌鲁木齐的列车上与摄影师林默、一对老夫妻、一个商人萍水相逢。一枚突然失窃的祖传玉佩，把这个封闭包厢变成了人心的试金石。
本段之前： 旅途第二日清晨，软卧包厢里一声惊叫打破宁静——老太太张姨发现自己那枚母亲传下的羊脂玉平安扣不见了。这一段正是失窃的惊慌与猜忌，在五个陌生人之间悄然埋下种子的时刻。
A week before finals, engineering student Leo is paralyzed by anxiety over a fragile balsa-wood bridge he can't get to hold. A workshop technician, a professor, and an old librarian each nudge him toward the same quiet lesson: build one sturdy thing at a time.
Before this excerpt: In the engineering workshop, Leo stares at his half-finished “Archimedes Bridge.” As he prods the flimsy joints, the technician Mr. Henderson and Professor Vance stop by his bench, offering advice on the truss and on Archimedes' famous “place to stand.”
A wealthy man is found dead beneath a toppled library ladder, a dusty copy of Moby Dick beside him. The weary detective Arthur Vance must decide who is lying: the composed widow, or the terrified young caregiver.
Before this excerpt: In the dead man's study, Arthur questions the two women who were in the house. The widow Eleanor coldly insists the caregiver Clara was “late” bringing her tea, while Clara stammers her account — and Arthur, kneeling by a suspiciously clean shelf, presses her on exactly what she heard.
Ten years after Liam left town without explanation, Elara returns to Blackwood Ridge for the Perseid meteor shower and comes face to face with him again. Beneath her sister's fierce protectiveness lies a truth about why he really left.
Before this excerpt: On the crowded ridge under the meteor shower, Liam walks up to Elara for the first time in a decade. Her sister Susan plants herself between them — “It's been ten years, I think we're past ‘hello’” — while Liam, undeterred, tells Elara she looks good.
While packing up their grandfather's house, a family is warned never to touch a small lacquered box on the mantel — the “Gifting Box,” which gives something back for whatever you put inside, but never what you expect.
Before this excerpt: In Arthur's dusty study on moving day, the old man forbids his skeptical son-in-law Mark from packing the little box. Leo asks what it does, and Arthur — knuckles white — begins to explain the eerie rule of exchange that governs it.
A tiny congee restaurant on Alder Street runs on habit and the quiet rhythms of its three workers. When the landlord threatens its survival, cook, owner, and prep-cook must find a way forward measured in ladles.
Before this excerpt: After closing, Maya, Ben, and Lena sit down to eat the congee together. Ben, who has been distracted over the ledger all evening, finally says it plainly: the landlord is raising the rent in January — enough that a bad winter could end them.