Masterpiece Mystery! Inspector Lewis, Series IV: The Mind Has Mountains

Kevin Whately returns as Inspector Lewis teamed with his cool, cerebral partner Detective Sergeant Hathaway (Laurence Fox). Lewis, the former working-class foil to the erudite Detective Inspector Morse, tackles murder and mayhem with the help of Hathaway.

In the 2011 season, Lewis and Hathaway tackle four cases in the seemingly perfect academic haven of Oxford: "Old, Unhappy, Far Off Things" (Originally aired Sept. 4, 2011), "Wild Justice" (Originally aired Sept. 18), "The Mind Has Mountains" (Originally aired Sept. 25, 2011, Repeats Aug. 26, 2012) and "The Gift of Promise" (Originally aired Oct. 9, 2011, Repeats Sept. 2, 2012).

"The Mind Has Mountains" - "Call the guinea pigs, would you," directs the brilliant psychiatrist Dr. Alex Gansa. The assorted subjects pile in to get their medication — all part of a week-long antidepressant drug trial taking place on the Oxford campus. The drug being tested is a form of ketamine — a horse tranquilizer and party circuit favorite.

When trial subject Amy Katz is found dead, the drug-induced veil of contentment starts to tear. Katz was the unwitting object of obsession for several other patients, under the dubious care of the morally questionable Gansa.

Lewis and Hathaway, aligned in their quiet distaste for psychiatry, uncover a number of provocative clues — condemning phone messages, notes and the remnants of a damning video diary made by the dead patient. The facts are furiously lining up. But in the mysterious realm of the human mind, sometimes certainty is deceiving.

Kevin Whately and Laurence Fox star alongside Douglas Henshall ("South Riding," "Collision") in "Inspector Lewis: The Mind Has Mountains."

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