I'm assuming you mean mission 7, right? Ok, I'm gonna help you withthe part that I got stuck on and hope that helps you out. After getting to the station in your phone man outfit (not to mention the hellish drive on the way there,) walk into the building and a guy will ask you what took you so long and you'll say traffic was murder (what a joker that Hammond guy

) This guy will lead you to the phone line room. Wait til he leaves you "alone" (or as close to it as you can get.) Once he's gone start back the way he brought you except take a left in the blue hallway. This is the hallway where if you start down it and cops notice you they will threaten to arrest you. Wait til no one is looking...you'll have a short window of time to slip through. There's a stare case to the second floor and go up there. Eventually you will find you're way to the Evidence room. It may seem hard to find the first coupl eof tries, but as long as you don't take detours through offices and don't get spotted you'll have plenty of time to find it. Actually it's easy. There's a gun in there which you will need. OK NOW HERE IS WHERE I GOT STUCK. It took me a while to realize the guy you are suppose to kill is the cheif talking to his bodyguard just around the corner when you come out of the evidence room (theyre talking about which interrogation room Yasmin is in.) Wait for them to start moving and start stalking them. Sooner or later he ditches the bodyguard in a computer room go around the other side of it so he doesnt see you. Keep following the cheif all the way downstairs (at one point he passes through an office so you'll have to resume stalking him again on the other side.) Once you're downstairs it's a breeze following him...people don't seem to question you and as long as you don't get too close he won't notice you following him. He'll take you straight to the interrogation room with Yasmin. Corner him in there and kick his azz.
The next part is pretty self explanatory. Just do what Yasmin tells you to do. OK, so maybe I could have looked up a guide for you, but this just made me feel special for some reason.
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