[2] McNab received her first notable acting role in 1991 when she appeared as a Girl Scout selling cookies in The Addams Family.

She played a more prominent role in the 1993 sequel Addams Family Values as snobby camper Amanda Buckman.

McNab had initially auditioned for the lead role of Buffy Summers, which went to Sarah Michelle Gellar, and instead she played Harmony Kendall, a vapid, popular high-school student who eventually becomes a vampire.

She briefly appeared in the 2010 sequel Hatchet II and afterward starred in a number of direct-to-DVD horror movies such as Dark Reel and Thirst, as well as the TV-movie Vipers alongside Tara Reid.

[4] McNab was the cover model for and was featured in a nude pictorial in the November 2006 issue of Playboy magazine.