Go to Arcade mode, combat challenges, the challenge called Hostage Situation.
Use the 1st guy Matter Stealth, Go through rolling and killing the enemies.
Throw grenades and flash grenades in hard areas and save the hostages.
You will get Good Samaritan after you save the first hostage.
You can also get Precious Cargo by saving the rest without them taking damage.
Even if they take damage you still get the achievement.
Here's a video of me doing it.