Lona Cohen (Russian: Леонтина Владиславовна Коэн, Leontina Vladislavovna Koen; January 11, 1913 – December 23, 1992), born Leontine Theresa Petka, also known as Helen Kroger, was an American who spied for the Soviet Union.

Lona Cohen was born Leontine Theresa Petka in Adams, Massachusetts, the daughter of Polish Catholic immigrants.

[3] George Blake, a British mole for the Soviet Union, claimed in an interview that Lona was a "very, very resolute woman, very determined.

Morris then hid the weapon inside a bass fiddle case and transported it into the Soviet consulate while avoiding detection.

As part of Line X, Lona conducted "technical, scientific, and industrial espionage", delivering and receiving documents along the East Coast.

She frequently received documents from seamen from South America and Europe, using her charm to persuade dock-workers to permit her access to the ships.

Later, Semyonov wrote an appraisal of Cohen, commending her love of the Soviet Union and her work with agent Link, eventually identified as Bill Weisband.

[9] As word leaked to the Soviets of the developing Manhattan Project, Lona Cohen was chosen by her new control officer, Anatoli Yatskov, to work as a courier.

Lona's job was to transport classified information from Theodore Hall, and a source cover named "FOGEL" and "PERS" from the American secret atomic weapons project at Los Alamos, New Mexico and carry them to the Soviet consulate in New York.

[14] Peierls had a Russian wife, as did his brother, and he maintained close contact with colleagues in the Soviet Union before and after the Second World War.

To avoid detection she concealed the report inside a Kleenex box, a move which became known within Soviet spy circles for its cleverness.

[16] After the defections of Elizabeth Bentley and Igor Gouzenko, the Cohens ended contact with Soviet intelligence until 1949, at which time they began working with Col. Rudolph Abel, a U.S.-based "illegal" (not using diplomatic cover for spying).

The Cohens went on many foreign missions for the Soviets during this time, traveling to Japan, Hong Kong, Australia, New Zealand, Austria, Belgium, and the Netherlands.

In the basement of their house, at 45 Cranley Drive, Ruislip, situated not far from the military airfield of RAF Northolt, they set up a high-speed radio transmitter and began sending Moscow "information of special importance".

One New Year's Eve, the Doels gave a party at which Lona Cohen (aka Helen Kroger):arrived looking very exotic in a long black evening dress.

[22] In 1983, the British playwright Hugh Whitemore dramatized the case as Pack of Lies, which was performed in London's West End theatre district starring Judi Dench and Michael Williams.

The plot centered on the neighbors (and seeming friends) whose house was used as a base from which the security services could spy on the Cohens, and the way paranoia, suspicion and betrayal gradually destroyed their lives during that time.