TV Guide for Yesterday Thursday 8 in Sky History 2

Experts scrutinise the engineering behind the Egyptians' Sphinx and pyramids. Could this advanced civilisation have received extra-terrestrial help.

Tasmania, New Zealand and the Bass Strait: Investigating the disappearance of pilot Frederick Valentich, whose last transmission gives an account of what he experienced.

In 1993, a teenage girl walking her dog in Shropshire, England, witnesses a cylindrical object in the sky. School kids in Florida report multiple UFO sightings in 1967.

Dozens of witnesses report seeing a fiery object falling through the Pennsylvania sky in 1965. In 1997, Phoenix residents claim to spot boomerang-shaped UFOs above their homes.

Andy explores Wiltshire's mysterious megaliths and barrows, visits a medieval meadery and encounters a religious pilgrimage at the site of a freshly made crop circle.

A look at one of Scotland's most popular paid tourist attraction. With a slew of sieges to its name, it is no surprise that the site boasts some formidable defences. (1 of.

Look down over a constant inferno in Turkmenistan, mysterious circles in the Namibian desert and secret electric blue ponds in Utah.

Discover South Korea's seaweed farms, visit an Alaskan town where everyone lives under one roof and check out a flooded passage that leads to the French island of Noirmoutier.

Bullet Proof Boobs, Amazing Coincidences, Directional Cows: Cows align with the Earth magnetic fields, and a young makes an incredible connection.

Millions mourned the death of Elvis Presley in 1977, but he's been spotted hundreds of times since.

Experts investigate whether a controversial union leader's disappearance is linked to the mob or if he went missing on his own accord.

The compelling series returns to examine more eerie reports of UFOs. Can it determine where in the universe such strange flying crafts could be coming from.

A look at frightening reports of alleged alien abduction, including cases in which abductees claim to have been subjected to torturous medical experiments.

February 1942, and the sky over Los Angeles erupts as anti-aircraft guns begin firing on strange targets. Could this have been an extraterrestrial raid? (1 of.

Travel to Queensland's farming country where rain-drenched crops meet the Great Barrier Reef. Is there a link between water and UFO activity.

In 1966, two Ohio police officers spot a strange light in the sky, triggering a chase across state lines. An ex-military man in Florida is knocked out by a beam of light in 1965.

On a country Texas road in 1980, a diamond-shaped UFO melts a vehicle below. In 1967, a man in Manitoba encounters a flying disc and reports hearing voices inside.

Andy receives military training at a Civil War re-enactment, before embarking on a ghostly hunt and meeting the man who captured leopard DNA from a sheep kill.

Dan Jones explores the history of Cardiff castle over more than 2,000 years and reveals how it transformed into a lavish Victorian home. (2 of.

Experts uncover a labyrinth that could lead them to the secrets of Imhotep.

Look down over a constant inferno in Turkmenistan, mysterious circles in the Namibian desert and secret electric blue ponds in Utah.

Discover South Korea's seaweed farms, visit an Alaskan town where everyone lives under one roof and check out a flooded passage that leads to the French island of Noirmoutier.

Bullet Proof Boobs, Amazing Coincidences, Directional Cows: Cows align with the Earth magnetic fields, and a young makes an incredible connection.

Believers and skeptics debate the origins and meanings of the mysterious formations known as crop circles.

Experts investigate whether centuries-old paintings of aliens and UFOs are artistic renderings of real sightings, a coded message for humankind, or just a coincidence.

Experts uncover a labyrinth that could lead them to the secrets of Imhotep.

This is the true story of how the German police were caught in a race against time to catch a depraved and psychotic killer.

Who Put Bella in Wych Elm: The dark tale of the skeleton of a woman found in a hollowed-out tree in Birmingham woodland, exploring the links between her and Nazi spy rings.

February 1942, and the sky over Los Angeles erupts as anti-aircraft guns begin firing on strange targets. Could this have been an extraterrestrial raid? (1 of.

Travel to Queensland's farming country where rain-drenched crops meet the Great Barrier Reef. Is there a link between water and UFO activity.

In 1966, two Ohio police officers spot a strange light in the sky, triggering a chase across state lines. An ex-military man in Florida is knocked out by a beam of light in 1965.