NGTV Guide: Thursday, September 16

The Vampire Diaries – the CW 8/7c
“Brave New World” – When a confused and desperate Caroline (Candice Accola) leaves the hospital and joins her friends at the Mystic Falls Carnival, Damon (Ian Somerhalder) wants to take immediate action, but Stefan (Paul Wesley) and Elena (Nina Dobrev) come to Caroline’s defense. Matt (Zach Roerig) is completely mystified by Caroline’s behavior, but still tries to tell her about his feelings for her. Damon has suspicions about Tyler’s Uncle Mason (guest star Taylor Kinney) and uses Tyler’s (Michael Trevino) volatile personality in an attempt to get Mason to reveal his secret. Upset with everything going on around her, Bonnie (Katerina Graham) takes her anger out on Damon.

Nikita – the CW 9/8c
“2.0” – Percy (Xander Berkeley) and Michael (Shane West) take their latest assignment, a Slavic leader wanted for war crimes, into protective custody. Nikita (Maggie Q) learns of their hideout and attempts to thwart their plan, but a mysterious group of mercenaries in search of nuclear material beats her to the task. Alex (Lyndsy Fonseca) is activated earlier than expected for a special assignment that throws her into the crossfire of bullets. A flashback reveals a pivotal moment in Nikita’s life.