Credit: Michael Desmond/The CW © 2011 The CW Network Photo: Silver Shoves Adrianna in 90210 Season 3, Episode 18: "The Enchanted Donkey"

Uh oh, 90210 'shippers! At least one couple is headed for a rough patch in Season 4. According to E! Online, Sean Wing, former star of the onetime ABC series The Whole Truth, will guest star as a scruffy graduate student/National Geographic freelance photographer who develops a crush on one of the series' attached gals. A love triangle will ensue, which could mean the end of one of our favorite pairings. The one consolation? Trouble arrives in a very handsome package.

Tune in on Tuesday, September 13, to find out who catches Sean's eye!

Source: E! Online