Plot hole: A central plot device in this episode is that there is no six letter word made up of the letters EXVIN, so the murdered man cheats at the word game by playing a word he knew to be inadmissible - exvin, a wine connoisseur who no longer drinks. Since he is supposed to be a stone cold killer player at this word game, don't you think he would have thought of Vixen? Sara Sidle points that word out later - why wouldn't a world champion word game player have figured it out, using a safe, common word and avoiding a possible challenge?
Suggested correction: If you watch the episode (timecode 00:36:20), in the flashback it shows exactly why he did not use vixen. There were 2 spaces between the "x" and the "n" on the board, so Adam played a bluff and used the fake word exvin.
Plot hole: In the end of the episode, Wolverine is seen recuperating after surgery removes the microchip in his brain, and his head is bandaged. Performing invasive surgery on Wolverine's brain isn't possible, since that would require going through his adamantium-infused skull and no conventional material is capable of that. Only a less invasive technique (such as going through the cranial sutres or cranial foramen) would have been effective and that most likely would not have required Wolverine's head to be bandaged (especially with his rapid healing mutant ability).
Plot hole: In the pilot, it is established that the surface of anything/anyone made invisible by "quicksilver" is freezing. (Darien gets caught in the women's shower because the mist freezes on him. He freezes the beer mugs for the doctors.) But in later episodes, nobody notices him standing invisible - and freezing!? - next to them.