Gossip Girl

(8 p.m. The CW)

Ever wonder what Lily van der Woodsen was like as a teenager? GG goes back to the ’80s and revisits the 17-year-old Lily (Brittany Snow), as she confronts a dilemma: Whether to marry into higher society, or run away with the rugged (but penniless) rock star Rufus Humphrey. Back in the present, Nate and Blair go to the prom together, but it’s not a night to remember — thanks to Chuck. No Doubt makes a guest performance.