Mysterious forces are at work in 1930s Tibet. The once gentle Yeti have turned savage and besieged a Buddhist monastery. The Second Doctor, Jamie and Victoria arrive expecting a friendly welcome from the abbot, but soon become ensnared in the plans of the extradimensional being known as the Great Intelligence.

• BBC
• Patrick Troughton
• Frazer Hines
• Deborah Watling
• Jack Watling
• Wolfe Morris
• Charles Morgan
• Norman Jones
• David Grey