The gang gives each other the most 2006 Christmas gifts ever, Lauren gets a phone call from an old flame, and Jason ruins everyone's New Year's Eve while smoking like a chimney.

Lauren is under a magnifying glass at Teen Vogue, Heidi celebrates an anniversary with Jordan and finally works the club, Whitney struts her stuff, and Frank and Meredith have one too many.

Whitney demonstrates her Drew Barrymore-ness, Audrina dates the show's biggest sleazeball to date, Lauren throws Jason a birthday party, and Meredith makes big plans for Frank's dating life.

Lauren channels her inner Cha Cha DiGregorio, Jason wins Lauren back with the art of conversation, and Heidi pays her dues at Bolthouse.

Lauren explores the world of inappropriate neckwear, Heidi paves the way for millennials at work, Jason leaves a voicemail, and Meredith learns that she is a 7.

Heidi lands her dream job, Lauren throws some serious shade, and Frank and Meredith discuss the all-important Hills theme song.

Lauren learns how to dress "Teen Vogue," Heidi interviews like a champion, the gang crashes a party, and Frank reminds Meredith of an infamous night out.