Old Friends - S1-E3
Continuity mistake: Near the end of the episode when Mike is threatening the Assassin, by withholding his allergy shot. The needle flips instantly in his hand between shots. Noticeable because of the black tip on one side. (00:39:05)
Old Friends - S1-E3
Other mistake: This Jan Haseck assassin, who has either multiple allergies or else one allergy to a very common substance (peanuts), could never do any espionage work, as it would make him too vulnerable.
Chosen answer: It might not actually have one, in which case, he'd have to go down into the club and use theirs. As for showering, going to his mother's house or a gym membership would take care of that.
Captain Defenestrator