Helen Moller is the name of two characters in the first season of the Starz Original Series Counterpart.
Moller is played by Lotte Verbeek. The character was known as "Ringleader" in all pre-show publicity in order to hide the true nature of the role.
D1 Helen Moller ushers Peter Quayle into a meeting in the Office of Interchange Diplomancy Department warning him that her boss has been in since very early in the morning and is on his "fourth cup". (See: The Lost Art of Diplomacy)
D2 Helen questions Oskar Wolfe after his unauthorized exit from the safe house. (See: Act Like You've Been Here Before)
D1 Helen is apparently killed off screen. D2 Helen assumes her counterpart's job at the OI and kills several co-workers in a heretofore unexplained part of the Indigo plot. (See No Man's Land (Part One))