What can you find on the good ship "Principia"? Perhaps the Gravitonium Fitz needs to save the world. The team searches for more of the needed substance so they look for former HYDRA scientists. This leads them to an old friend of Mack's that he calls Candyman. But when they find out the gravitonium ended up on the bottom of the ocean on a sinking ship, they struggle to find it. That's when Deke, who's been trying to find his place while staying out of the way, thinks of an idea. The gravitonium became supercharged and is now floating miles above the earth in the ship. Meanwhile, Ruby Hale tries to get close to Werner von Strucker so her mother can use his abilities for her new team. And Ruby is very good at what she does. Yo-Yo is struggling to cope with her new situation, but Mack is looking for some supplies that could at least give her a hand (or two). Jay and Josh can't touch this on this week's Agents of S.H.I.E.L.D.: Case Files.