Stefan returns home late after a class reunion, claiming he spent the night at a classmate's place. His partner confronts him about his whereabouts, suspecting dishonesty after noticing a suspicious mosquito bite. Stefan insists he had a few drinks but promises not to stay out late again. Tension escalates when his partner demands the truth, questioning who the mysterious man is behind the bite. The episode ends with Stefan unable to fully explain, leaving their trust shaken and the real truth hanging in the balance.