On Monday night, Bristol Palin makes her "acting" debut on The Secret Life of the American Teenager.

However, the incredibly dramatic promo below for this episode (titled "Which Way Did She Go") doesn't touch on this unusual cameo. That's because it's too busy building some major suspense.

After all, when a certain secret that "they never saw coming" gets out... no one's life will ever be the same! Watch now, brace yourselves, people...

[video url="http://www.tvfanatic.com/videos/which-way-did-she-go-promo/" title="Which Way Did She Go Promo"] [/video]

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.