Just a Prick

Empty Hypos #1: Head to the left of Tannis's lab. You'll find a dartboard hidden behind a curtain. The first Empty Hypo is pinned to it.

Empty Hypos #2: Go back past Tannis's Lab. Look for a pipe; the second Empty Hypo is pinned to it. You might need to jump on the pipe to get the interaction prompt.

Empty Hypos #3: From where you found the second one, cross the ship to room PJ-331. Inside, on the left side of the door, there's another Empty Hypo stuck in a statue's eye.

Empty Hypos #4: Now, head down to the second floor and make your way to Moxxi's Bar. The fourth Empty Hypo is waiting for you right on the bar counter.

Empty Hypos #5: Go towards the stairs leading to the Cargo Hold, but don't go down yet. Instead, hang a left. You'll find the fifth Empty Hypo pinned to a poster between two lockers.

Empty Hypos #6: From those lockers, enter the crew quarters. The sixth Empty Hypo is pinned to a fuel pump just outside the second room on the right.

Empty Hypos #7: Now, descend into the Cargo Hold. Once you reach the bottom, turn around. The seventh Empty Hypo is pinned to a TV screen behind the stairs.

Empty Hypos #8: For the last one, find Claptrap's room in the corner of the Cargo Hold. The final Empty Hypo is with him.

Return Hypos to Tannis: Once you've collected all 8 Empty Hypos, return to Tannis's lab. Place them on the tray in the middle of the room to complete the mission.