WPGC’s six-hour birthday party at the 9:30 Club on Thursday night featured sets from more than a half-dozen acts both recent and vintage, but it was the crazy-prolific R&B hitmaker (and newly crowned Avon cosmetics spokesmodel) Keri Hilson who got to bat cleanup. Her hits-dense, rigidly paced 35-minute set culminated in “Pretty Girl Rock,” a hard-to-resist number that appropriates its chorus (“Don’t hate me because I’m beautiful”) from an old shampoo ad slogan.

Hilson was a frequent presence on the charts as a songwriter and arranger before she launched her performing career in earnest. Unlike B.o.B., the Atlanta rapper who preceded her onstage, Hilson didn’t bring a band, just a DJ/hype man, two dancers and a drummer. The heavy presence of prerecorded elements in Hilson’s set, backing vocals included, made it difficult to parse what her live singing contributed, so jams such as “Gimme What I Want,” “The Way You Love Me” and “Get Your Money Up” sounded indistinguishable from their recorded versions, which all sound pretty great.

Hilson’s pre-encore departure seemed unnecessary in a set this short, but it gave her hype man an opportunity to prime the crowd before the star returned, sipping tea, to sing (I assume) the breakups-won’t-kill-ya anthem “Knock You Down” and then “Pretty Girl Rock.”

For that last one, Hilson chose three women from the audience of varying shades and shapes to dance along with her. One of them appeared at Hilson’s side before her cue, providing a rare extemporaneous moment. Hilson politely gestured for the girl to return to the wings till it was time. And when the time came, the performer and her audience picks illuminated the song’s message, that we are all of us pretty girls.

Klimek is a freelance writer.