Stop Me Before I Hug Again - S1-E13
Character mistake: In Brian's "Laws I Have Broken Since Joining FBI" list, item #30 misspells the word "recorded" - "30) Recoreded NFL Game Without Consent." He'd only have that knowledge if he was using NZT, and if he was, he wouldn't make a mistake like that.
Continuity mistake: Rebecca tells Brian that Chris received the call from his brother to meet and hand the bag off at the park at 4pm. In the next scene, Brian says, "Chris wasn't handing the bag off until 6, so I went straight into training." 2 hour time difference there.
Character mistake: When talking about Mike and Ike giving them descriptions while on NZT, he mentions that he once heard Ike's name but forgot it. Completely impossible since his memory is impeccable on NZT.