《探长薇拉第四季》剧情解析：每个案件的核心是什么？

简介：The DCI Vera Stanhope, assisted by her trusted colleague DS Joe Ashworth, steps up for another series of challenging cases. She investigates the mysterious death of a pensioner on a busy commuter train (On Harbour Street), unearths a thirty year mystery after a brutal murder on the sands of a seaside resort (Protected), delves into the tangled life of a businessman found floating in the water under the Gateshead Millennium Bridge (Death of a Family Man). Inspired by the novels written by renowned crime writer Ann Cleeves, and filmed against a backdrop of outstanding Northumberland landscapes and atmospheric production, each enthralling story is enhanced by the captivating performance of Brenda Blethyn as this shambolic yet brilliant detective.