The conflict in Vietnam, racial tensions, and a pair of shocking assassinations in 1968 threaten to fray the social fabric of America beyond repair. NASA tries to stay on track and meet the deadline JFK set to send a man to the moon and back. Through rare archival interviews, images that still resonate with wonder, and objects from the Smithsonian Institution, see how Apollo missions 7, 8, and 9 set the stage for humankind's greatest voyage.