In summary,here the events that happened during that hour:
1.Renee Walker is shot and killed by a sniper in Jack Bauer's apartment. Jack Bauer demands Dana Walsh's evidence implicating the Russian government in the day's attacks. Under threat of death, she gives him the bank where she stored it, but pleads that she had nothing to do with Renee's murder.
2.At the bank, a flash-bang Dana hid in the safety deposit box incapacitates Cole Ortiz, allowing Dana to take the data card for herself.
3.President Charles Logan reassures President Taylor that Bauer can still be stopped, and recommends appointing his aide, Jason Pillar, to lead that effort at CTU New York. In secret, he allows Mikhail Novakovich access to Pillar's intel so that his covert operatives can eliminate Bauer themselves.
4.Jason Pillar successfully locates Jack Bauer at the bank and relays the information to Pavel Tokarev.
5.Police attempt to apprehend Jack, but he escapes and pursues Dana Walsh to a construction site. After a stand-off, he takes the evidence from her, then kills her in cold blood.
Killings continue as Renee gets murdered and Dana Walsh,the CTU mole,gets killed by Jack after extracting information from her.It is obvious that Day 8 is definitely the most violent season of 24.