Wachs can't catch a break (SPOILERS!)
Sheesh, poor Dr. Wachs seems fated to die. In the original novel he's killed in the same accident that leaves Nick invisible, by an explosion, and in the movie he's injected with poison by Jenkins' henchmen.
So, if he doesn't die in a lab accident he gets murdered by government spies. Poor guy. Although in the book he is admittedly kind of a jerk (not that Carillon didn't deserve the thrashing Wachs gave him).
Speaking of which, Wachs makes a lot of sense when he says to Jenkins, "I want to find him as much as you do, so what are we doing here?" Jenkins ignores this proposition and has his men murder the good Doctor, ostensibly to keep Nick's existence known only to himself (and Singleton).
But...considering Wachs is a pretty meek college professor it should be easy enough to boss him around, and having an actual scientist on your invisible man hunting team seems like a good idea. Could even use him to lure Nick in with the hope of a cure.
The story possibilities of a Wachs/Jenkins teamup would've thus been interesting in that light, but instead they just have Jenkins kill him to make Jenkins look more villainous. Pity.