Ancient Aliens 17, Encounters

Special episodes counting down the top 10 of everything from mysterious sites around the world to mystifying artefacts and cover-ups.

A countdown of the world's top 10 most mysterious sites, from the blocks of Stonehenge to the stones of Puma Punku.

Special episodes counting down the top 10 of everything from mysterious sites around the world to mystifying artefacts and cover-ups.

Special episodes counting down the top 10 of everything from mysterious sites around the world to perplexing artefacts and cover-ups.

Shatner meets with leading experts to ask some of the most pressing questions about human origins, the cosmos, archaeology and otherworldly beings.

It is humankind's most profound achievement: blasting off into the stars. But is it possible that our voyages into the cosmos are really a return to our true origins?

Since the 20th century, scientists, journalists and investigators have been documenting UFOs. Today, there is even more proof of extraterrestrial visitation.

An investigation into amazing ancient sites built with acoustic purpose, indicating that their builders could have been aware of a harmonic code.

Peru - famous for its prehistoric ruins - is one of the most mysterious places on Earth - but could it also be a site of extraterrestrial visitation?

A look at Mount Shasta in northern California, which is rumoured to be a hotbed of strange events and otherworldly visitors from Bigfoot to UFOs.