Friend or Foe?

Friend or Foe? is a mission in Grand Theft Auto: Chinatown Wars given to you by Hsin Jaoming.

Strategy
Head to Hsin's place and you'll be met by someone else who orders you into a van to start driving eastward. You're lead to a set of explosives in a back alley and will need to get out of the van to collect them before hopping back in and driving to the next destination.

Now drive to the Korean gangsters' hideout to hit the waypoint. You need to get out of the van and set the explosives near a wall using the touchscreen to plant and arm the bomb. The explosion blows a hole in the wall through which two men walk in, and you're left to hop back in the van and back it up to the hole in the wall.

Next, you need to defend the entrance to the back alley so walk to the new waypoint and take cover near the wall at the entrance. Gangsters will roll up in cars and get out to try and enter the alley. Take 'em out—Molotovs and a sword work well—and watch the radar for a group of enemies that enter from the opposite side of the alley. Wipe them out (you'll need a Molotov or grenade for this) and then get back in the van.

Drive back to the garage that's now your GPS destination and expect some weak resistance on the way. Ignore the Korean gangsters' cars and just drive to enter the garage. As you enter the garage, a touchscreen mini-game challenges you to crack the safe. Place the stethoscope on the safe and then rotate the dial until you get the stethoscope to beep. A button on the instrument will blink when you've got the right position, prompting you to press the button and lock in the number. Then start rotating the dial the opposite direction to find the next number. There are three numbers to find and when you've got them all locked in you'll complete the mission.