This article contains plot spoilers for the 2017 series of Twin Peaks.
Dwight Murphy was the warden at Yankton Federal Prison.
In the 2010s, following the arrest of Dale Cooper, Murphy led FBI personnel Deputy Director Gordon Cole, Agent Albert Rosenfield, and Agent Tammy Preston to Cooper to interview him. Following the interview, Cole advised Murphy to give Cooper his phone call and to fill him in on the details.
While left alone for his phone call, Cooper mused about calling a "Mr. Strawberry," intimidating Murphy. He then punched in a series of numbers which set off the prison's alarms until he hung up, saying "the cow jumped over the moon," confusing Murphy further.
Cooper later requested a meeting with Murphy, who kept a gun trained on Cooper, who revealed that the legs belonging to the same dog as the one found in Cooper's trunk during his arrest had been sent to two people who would be summoned if something happened to him. Cooper then mentioned a "Joe McClusky," thus blackmailing Murphy, demanding release from the prison along with Ray Monroe and a car to be provided for them along with a gun in the glove compartment. Murphy complied, releasing Cooper overnight.
Murphy later called Cole, telling him that Cooper had escaped.