In 1969, a serial killer taunts investigators with cryptic ciphers, leaving police and the public questioning his identity for over 50 years; new evidence and technology may finally be able to crack his code and discover who the Zodiac Killer is.

11:00 AM on History Canada East

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History's Greatest Mysteries The Loch Ness Monster

Despite centuries of sightings and searches, one deep-sea monster remains unidentified; as evidence continues to mount, the mystery endures as to whether the Loch Ness monster exists.

12:00 PM on History Canada East

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History's Greatest Mysteries Unlocking the Secrets of Stonehenge

It's one of the most famous prehistoric monuments on Earth -- a mysterious arrangement of stones that have adorned the English countryside for millennia; nobody knows how the landmark was built or why.

1:00 PM on History Canada East

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History's Greatest Mysteries The Unabomber: Case Closed

A twisted mastermind uses homemade bombs to terrorize the nation.

3:00 PM on History Canada East

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History's Greatest Mysteries The Killing of Bugsy Siegel

Notorious mobster Bugsy Siegel is gunned down in his Beverly Hills living room; Siegel's killing becomes front page news; no arrest is ever made.

6:00 PM on History Canada East

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History's Greatest Mysteries The Unabomber: Case Closed

A twisted mastermind uses homemade bombs to terrorize the nation.

8:00 PM on History Canada East

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