By Kenneth Scearce
In the Zapruder film, the earliest obvious reaction we can see to the commencement of the assassination is that of Rosemary Willis. Rosemary Willis was 10 years old when 
she witnessed President Kennedy’s murder. She can be seen in the Zapruder film after it resumes at frame 133, running along the south side of Elm Street, in a red skirt and a white, hooded jacket. During the first 5 seconds of the restarted film, Ms. Willis turns her gaze away from Kennedy towards the Book Depository, slows from a run, and stops abruptly. Her body language clearly strikes a pose of thunderstruck bewilderment while almost everyone else visible in the Zapruder film appears nonplussed.
The two animations below were created by Gerda Dunckel from the Zapruder film (the copyright of which is owned by The Sixth Floor Museum). The animations run from the Zapruder film’s first frame, Z133 to Z221, ending just before the second shot was fired at Z222.
The first animation is a close-up focused on Ms. Willis:
The second animation is an extreme close-up of Ms. Willis:
Initially, during frames 133—160 of the Zapruder film, Ms. Willis keeps time with the president’s Lincoln Continental. Soon, however, certainly by no later than Z161, Ms. Willis begins to slow down noticeably (her swinging arms have dropped by Z161 as she slows, compared to the height of her arms in previous frames). By Z197 (and probably earlier), Ms. Willis has come to a complete stop. During this sequence, Ms. Willis is facing in the direction not of President Kennedy to her right front, but of the Book Depository to her right rear. This is very odd—unless something more significant than watching President Kennedy had caught her attention.
