Head back into the metro to travel to the Ruzicka Station. You'll run into Smiley as soon as the Metro arrives. He wants you to get into a crime scene and nab some evidence.

Make your way to the waypoint. An officer will tell you that you can't come in and that the area is restricted. That's just code for "find another way in."

There's a locked room to the left and to the right. The room on the right has a laptop that you can hack. The room on the left has a vent that will get you inside the restricted area. Enter the room on the left. The vent will take you right into the path of two guards. Use your Glass-Shield cloak to pass them. Hug the wall on the left. They are easy enough to pass from that position.

Head up the steps toward the waypoint and the double door. Don't go into the main room straight ahead. There's another vent in the room to the left. Go through it. Make your way past the guards, hugging the wall the entire time. The Glass-Shield cloak is your best friend. Use it wisely to slip by any guards in your way while you crouch to the waypoint.

Pick up the evidence, and then head to the next waypoint to leave the area. There are two guards blocking the exit. Throw something away from you to get their attention, and then slip by using the Glass-Shield cloak.

Next, bring the DSD to Smiley back at headquarters. This will complete the mission.