The Crew

Jim Lovell
Marking his fourth and final trip into space, Jim Lovell was chosen to command Apollo 13 which was to be the third mission to land on the moon. 

Fred Haise
Fred Haise made it his business to know as much about the Lunar module as the team who designed it.  Fred Haise was chosen as Lunar module pilot for Apollo 13.

Jack Swigert
Jack Swigert was the backup command module pilot who was promoted to prime crew when
pilot Ken Mattingly (who was originally to go on the Apollo 13 mission) was exposed to German measles.  The flight plan called for Swigert to remain in the command module while the two astronauts, Lovell and Haise, explored the moon's surface.

Gene Kranz (flight director)
Gene Kranz (who was NASA's lead flight director) was the unquestioned boss of Mission Control during the Apollo program.