Here’s the synopsis for 90210 episode 4×06 – Benefit Of The Doubt. Do not read if you don’t want spoilers!

TUESDAY, OCTOBER 18
“90210″ – (8:00-9:00 p.m. ET)
“Benefit Of The Doubt” (TV-14, D) (HDTV)

KELLIE PICKLER GUEST STARS – Liam (Matt Lanter) gets offered a modeling job after an agent sees the commercial for his bar, while Annie (Shenae Grimes) finds herself starting to fall for an unlikely guy. During a charity talent show event to raise money for an experimental cancer treatment for Raj (guest star Manish Dayal), Naomi (AnnaLynne McCord) is determined to win the contest in order to show up Austin’s (guest star Justin Deeley) out-of-town visitor Sally (guest star Kellie Pickler). While working on his music, Dixon (Tristan Wilds) pushes his limits and starts spiraling out of control, which forces Adrianna (Jessica Lowndes) to confront him. Gillian Zinser, Jessica Stroup and Michael Steger also star. James L. Conway directed the episode written by Liz Phang (#406).

Source: CW