Expert witnesses analyse nettles and soil to catch the killer of the Soham schoolgirls, new DNA techniques finally solve cold case murders, and ballistics techniques are demonstrated.

A forensic art expert proves paintings by a well-known artist are fake, blood spatter patterns in a hotel help catch the killer of a father of three, and there's a fingerprinting masterclass.

A DNA expert witness helps solve a 50-year-old crime, a murder investigation is solved by tracking unusual blue fibres around the world, and forensic anthropology is explored.

Text message analysis reveals a shocking crime, and DNA on old evidence catches a killer. Soil science and the first murder case solved using DNA evidence are also explored.

Expert witnesses use fibre and DNA evidence to solve three violent cold cases in Pembrokeshire, a gemmologist exposes a diamond investment scam, and Ashley visits a toxicology lab.

Ashley John-Baptiste is taken to a mock crime scene and learns from a crime scene expert on the importance of the role, and is shown how to preserve, examine and analyse a scene of a crime.

Blood traces hidden under paint help an expert witness overturn a miscarriage of justice, an unusual gait identifies a killer and the science of fibre evidence is explored.

After 32 years, expert fibre analysis helps to bring the killer of two Brighton schoolgirls to justice, and the analysis of bones found on a Yorkshire moor helps to find two killers.

Marks left by a shoe help detectives catch a killer, a forensic linguist deciphers digital messages, revealing a murder plot, and the power of blood pattern analysis is examined.

A serial killer is caught by using soil analysis, insects hold the clues to finding a murderer and the forensic sciences of hair evidence and entomology are put under the microscope.