When Barbara has to take her mother to the rest home. Her sense of guilt at having to abandon her mother is palpable, especially as her mother has no idea what's happening to her. To make it worse, Barbara sees a program on TV on how animals dumped by their owners at SPCA look forward to be taken in by new owners. It makes Barbara realise that her mother has no other home to look forward to.
The scene where Barbara rips into Lynley for having her house re-painted without telling her — she's moved her mum into a home and is selling the house to get a flat of her own. The action trips Barbara's horrible guilt over moving her mother in the first place, to the point where she calls herself "an inadequate human being". He apologises for his presumption, but also tells her flatly that "one thing you are not is an inadequate human being!"
Lynley's grief over Trenarrow's death. What's awful is that he knows that for all these years, he prevented his mother from marrying Trenarrow, and now that he was finally reconciled to the idea, it's too late.
Havers' utter disillusionment at the end. It takes a heart of steel to watch her Trying Not to Cry as she tells Lynley how much DI Barlow meant to her and how terribly let down she feels.
Not to mention the moment when Hadiyyah is harassed at an amusement park by racist Britons. Barbara intervenes and is then herself harassed by Pakistan boys who thought she was the one bothering Hadiyyah. It takes Azhar intervening for them to go away, snapping at him for defending her. The distraught look on Hadiyyah's Perpetual Smiler face just kills you.
When Lynley is told that Helen has miscarried. In the next scene, he blames himself for what has happened because when he first heard the news about Helen's pregnancy, he had been in two minds about whether he was really happy about becoming a father. Havers does her best to lessen his sense of guilt.
The now-useless book on baby names and Lynley's forlorn expression as he looks at a baby in a young woman's arms, as she tells him what she's naming the baby.
Barbara's seemingHeroic Sacrifice. Lynley's reaction is heartbreaking - all he can do is desperately cry Barbara's name.
Barbara collapsing in tears and sobbing hysterically into Lynley's chest in the aftermath of being held hostage at gunpoint on her first case back from being shot in the line of duty the previous episode. The way he holds onto her as though he'll never let go makes it worse. They're terrified and clinging to each other as though they have nothing else to hold on to, and Nathaniel Parker and Sharon Small make viewers feel every bit of it.