I remember watching this hollwood movie as a child (I'm 21 now) and I was impressed, so:
In the prologue like section of the movie our protagonist is this cocky, young, skilled, white skinned agent with dark hair (probably a FBI or CIA agent -- a government agency with uniforms as I remember) makes a mistake/rushes things (during a heist? not sure - and maybe it was his friend who makes this mistake) and something bad happens (maybe some hostages get killed and/or his colleagues die but I'm not sure about this) and he gets fired by a superior in his office of course (Also his friend(s) may get fired alongside him -- and maybe the antagonist holds a grudge?). So he gets a job as a janitor back at the agency.
The scene I remember takes place some time after (not sure maybe years or even a decade after the lay off) he gets the janitor job.
So, he's being mocked by a group of cocky recruits and since he was an excellent agent he demonstrates his skill and they're either impressed or mortified/embarrassed and the only guy who remembers him being a part of the agency also observes this occasion. He was an old white man, I'm not sure what his job was.
In the end (if this movie is the one with the protagonist's colleague/friend is antagonist) protagonist and the antagonist may have a showdown and antagonist is either killed or brought to justice by the protagonist.
Also both the protagonist and the old man are high profile actors.
Sorry for the block of text but I've been looking for this movie for a while. I tried to make it readable with the over-abundant use bold and italic characters even though it is ill-advised. Underlined the parts I remember most vividly and of course the italics are my notes. I was born in 1996 and watched this movie on TV so maybe a year after it came out? Which would put the release window around 2000 ~ 2006 or even 2007.
Thanks in advance. Have a nice day.