10 Most Messed Up Deaths In Star Trek: The Next Generation
2. The Polymerisation Experiment — Lieutenant Hagler
There are yet more spooky goings-on for the crew of the Enterprise-D in Schisms: Riker's having trouble sleeping, and it's not because of his cooking; Geordi's losing connection; Mot's losing his grip on the scissors, and Data's losing his chronometer. Warm milk's not going to solve this one, Doctor!
A Polymer's Doom
Then we went to a room for some time and observed,
Why a handful of crew from the ship were perturbed.
By the clicks and the ominous light overhead,
We did miss the lieutenant not tucked up in bed.
That's not quite the poetic heights of Data, if heavily inspired by the android's slightly soporific verses, but hopefully you get the point. Lieutenant Edward Hagler probably just wanted some peace and quiet in his fancy pyjamas, but instead he was kidnapped and experimented upon by a gang of Solanogen-based lifeforms from subspace. Whatever they did to him, his "blood was turning into a liquid polymer" by the time Doctor Crusher made it to his quarters.
The last we saw of Hagler he was heavy heaving through his blue-grey deoxygenated face. We only know he died because Riker remembered to mention that fact near the episode's end. Not much of an epitaph, certainly not very poetic, but definitely messed-up!