It was probable that Sulu shouldn't automatically trust guys handing him necklaces that need to be contained in secure vaults, but he could always chalk it up to living life on the edge. He took it from Ianto and gave it a brief once over, before giving Ianto a skeptical look. "Promise it's not going to kill me in some horrible way?" he asked, even though he was already putting it on. Hey, what the heck.