Q.E.D Season 20 Episode release dates & where to watch

1. Breathless

This week an investigation into a controversial new drug-free treatment for asthma. The Russian professor who devised the theory, called Buteyko, claims many asthma symptoms are caused by hyperventilation, and therapists usingthe method encourage patients to slow down their breathing

2. Prisoners of the Forgotten Plague

The first of five new documentaries looks at a mysterious disease, known as sleepy sickness, which left thousands of people motionless and speechless in the 1920s. Now "virus hunter" Professor John Oxford fears there could be another outbreak

3. Deadly Secrets

Every year at least 20 women in Britain kill their babies on the day they give birth. The actual figure may be higher because many of these women manage to hide their pregnancies from everyone around them. Here, two women describe what led them to commit neonaticide, and psychiatrists try to explain why mothers do it.

4. The Quest for the Quagga

This week's film reports on how scientists in South Africa are trying to resurrect an animal extinct for more than a century-the half-horse, half-zebra quagga - in a project that inspired the film Jurassic Park.

5. Spontaneous Human Combustion

The last programme in the current series investigates a number of extraordinary cases of people bursting into flames. Scientists and fire experts try to explain the phenomenon, and there's an experiment aimed at showing how it could happen.

6. Hope for Helen

7. Bubble Babies

The science series returns with the first of five new documentaries. This programme tells the stories of children with severe combined immuno-deficiency, or SCID, a genetic disease that prevents babies from fighting infections. Two years ago, a revolutionary operation proved for the first time that this fatal disease could be cured.

8. Betsy and the Bongo

9. Call of the Deep

Free diving is a form of competitive swimming that involves staying deep underwater for long periods onjust one breath. Although free divers train themselves to overridethe desire to surface, it is possible that their stamina may be due to "dive reflex", the same instinct that enables babies to breath underwater automatically. Tonight's programme follows the British free diving team as they are tested to verify this theory.

10. Secrets of the Cloud People

The discovery in the Amazon jungle of a cliff tomb containing 200 mummies has given new credence to legends about a lost civilisation -the Cloud People. The tomb is nearto an ancient jungle city, found and filmed by explorer Gene Savoy, which includes a massive fortress. Savoy, a real-life Indiana Jones, reveals startling evidence that links these mummies to the ancient civilisations of the Middle East.

11. The Bionic Woman

Eight years ago Julie Hill was paralysed from the waist down in a car crash, but subsequently she was chosen to be the first patient in the world to receive electronic implants that might help herto walk again. Like a character from a science-fiction film, she has become a "bionic woman". This film follows her remarkable progress as a team of British doctors and scientists re-writes the anatomy text books and pushes back the limits of technology in an attempt to achieve her dream of walking.

12. Joella's Journey

13. Saving Trudy