In the third episode of the four-part story "The Power of Kroll," the Doctor (Tom Baker) and Romana (Mary Tamm) are forced to deal not only with the superstitious natives of the swamp moon of Delta Magna, but also with a gun smuggler named Rohm Dutt, who has been attempting to foment violence that will benefit the owners of a despotic Methane refinery. Adding to the Doctor's headaches is the fact that he has yet been able to locate the all-important fifth segment of the Key to Time. Written by Robert Holmes, "The Power of Kroll, Episode 3" originally aired on January 6, 1979. ~ Hal Erickson, Rovi