This video on youtube shows a girl volunteering for an experiment. When the serum is injected into her she beings to grow. The growing girl tries to evacuate but before she makes it out she becomes too big and bursts through the building. As she crashes through the build almost all the tiny people of the street bellow run away from her. The giantess closes in on one tiny man crushing a car as she goes causing the tiny man to run away. When the tiny man changes direction the giantess tries to grab him and when she misses she begins to chase him through the city. When she finally grabs him she hovers him over her mouth and drops him in.
You can watch this video here http://www.youtube.com/watch?v=VaIe4ZooHwo