Walt Cummings in Season 5
|Portrayed by||John Allen Nelson|
|First appearance||Day 4: 11:00 PM – 12:00 AM|
|Last appearance||Day 5: 1:00 PM – 2:00 PM|
 Day 4
When Charles Logan became the President of the United States following President Keeler's plane crash, Cummings was his Chief of Staff. He frequently had run ins with Jack Bauer, and when he found out that Jack had led a raid on the Chinese Consulate, Cummings sent an agent to CTU to kill Jack Bauer, in case the Chinese were able to capture Jack and get info out of him. This plan failed as Jack escaped with David Palmer's help.
 Day 5
In Day 5, it is revealed that Walt Cummings played a role in the assassination of David Palmer. He also implanted a mole within CTU to kill Jack Bauer, but Jack discovered this, and got info from the mole, Spenser Wolff, to find out Cummings' involvement. Walt Cummings was then detained and tortured by Jack, and disclosed that he had given the terrorists Sentox nerve gas, but hoped to detonate it in Asia, to reveal Weapons of Mass Destruction.
It then appears that Walt Cummings commits suicide by hanging himself. But later on, when it's revealed that President Logan is behind the conspiracy, we learn that Logan actually had Walt killed and he didn't commit suicide.