Revealing mistake: "Stop When Red Lights Flash": In the cell with Kate, Weston puts on his mask, making only his head visible. But the blue-screen matte used for this special effect is, weirdly, showing through his blue eyes.
Plot hole: "Sight Unseen": Wells has the key to Lori's shackles. Weston, who knows this, knocks Wells out, but instead of taking his keys, uses a completely unnecessary (and considerably more difficult) set of bolt cutters to break the leg cuffs.
Revealing mistake: "Man of Influence": Weston sends the big black Lincoln Continental over a cliff. It's still a Lincoln on the way down, but then stock footage cuts in as it explodes, and it's suddenly a completely different car.
Continuity mistake: "Man of Influence": The invisible Weston follows Geed into the parlor. When the door closes, there's no key in the lock. Then the shot cuts to a close-up of the door, and a key has appeared there, just in time for Weston to turn and lock it.
Continuity mistake: "Stop When Red Lights Flash": The invisible Weston spies on A.J. and Charlie as they open the safe, observes the combination, and then waits until they leave to open the safe himself. But the combination he dials isn't the same one they just used.
Continuity mistake: "The Klae Resource": Weston socks Fielder in the stomach and then in the jaw. He falls on the plush carpet, and doesn't hit his head when he goes down, yet he's rubbing the back of his head when he comes to, and not his jaw or stomach.
Continuity mistake: Pilot: Weston restores his "visibility" with gloves, a mask and special contact lenses. But when he removes the mask in the back of the van, the eyes are visibly part of the mask itself (with no eye holes), and not separate lenses.
Continuity mistake: Pilot: Walter signs his name on Weston's work order. But when the shot cuts away from him and then back, he's finishing the same signature that he just finished in the previous shot.