DI Susan Alembic and DS Luke Stone investigate the sniper-shooting of a young man in his flat, while DCs Alison Bain and Frank Craven deal with a hit-and-run killing.

A teenage couple kiss one another goodnight when the dead body of a woman is thrown from the top of an apartment block, killing the young man. DC Bain links the dead woman to a dating agency for married people, and DI Alembic goes undercover as a client.

One young woman is strangled as she lets herself into her flat, while across town another wakes to find her boyfriend has been shot while she slept.

The butchered body of a woman is found in a rubbish dump and the investigation into her murder leads Susan and Luke onto the trail of a baby-smuggling operation based in the Ukraine.

The owner of a gallery specialising in Islamic art is discovered in the boot of a submerged car. Armed with a clue found in the dead man's flat, Alembic and Stone head for a casino, but their investigation is destined to end in further tragedy.

A teenaged girl is found dead in her school with her wrists slashed, while a man has been tied to a tree and shot dead in the woods nearby. Stone and Alembic lead separate investigations, but is there a connection?

A 25-year-old woman and her lover are found dead in a hotel room, shot through the head with with the same single bullet. The man, Alan Scobie, is identified as a notorious criminal on remand for manslaughter, but it isn't clear which of the two was the original target.

A wealthy Turkish businessman killed in a drive-by shooting at first appears to have been an unlucky casualty of a turf war between Kurds and Turks, until a pathologist's report reveals that he had died of a heart attack before being shot and had also been poisoned.

When an unearthed skull opens a murder investigation, Stone orders a facial reconstruction of the skull and the photographs go to press, prompting a woman to come forward claiming that the face in the photo belongs to a man who raped and strangled her sister several years earlier. When Dumfries informs them that a different man was convicted of that murder, Stone and Alembic dig further and unearth a web of lies surrounding the previous investigation.

When a 16-year-old girl disappears from her home, leaving a blood-spattered bedroom behind, Susan and Luke start trying to track down the missing teenager, hoping that she may still be alive. Meanwhile, the mysterious death of a City trader who is shot in the neck with an arrow proves a tough case to crack.