During the limo ride at the beginning of the Studio level, the blue-haired guy will ask you to hand over your katana so he can split the coke with it. Give it to him and then proceed through the rest of the dialogue. You will then have to complete the first section of the Studio level without your katana, but there are enough throwables provided so that you're able to make it. On the next screen, the guy will leave your katana next to the elevator. Pick it up and the achievement will unlock.