Music critics show up at a gig on a d20 roll with a result of 1. They can show up at any club at any time, and it's hard to notice them among the band's following, casual strangers, and bar-hopping groupies. Music critics look like any other person - they don't dress in a suit and tie or little black dress. They might have tats, or piercings, or strange hair, just like any other patron, and can be of any gender, race, and orientation. For every gig, roll a second d20. On a roll of 1, someone in the band will 'see' the critic, whether or not a critic is actually there. If they *do* roll a 1, and a critic is there, the critic will be properly identified. Otherwise, they are deluding themselves.
If a critic is in the audience, they will write a review, so take the raw Performance and Show scores for each aspect of the gig. For every 3 scored, the critic will write something positive, and for every 1 or 0 scored, they will pan that aspect in their review. If there are more positives than negatives, the overall review will be positive, and the band will gain 40 points of Notice, and each member will gain a Hope. If the negatives outweigh the positives, the overall review will be negative, and the band will lose 40 points of Notice, and each member will lose a Hope.