Tandy, born in Fremont, California and raised in Fontana, graduated from Etiwanda High School in Rancho Cucamonga. She was a student at Chaffey College where she studied Business and Film Production, and is the first student from this school to win the Miss California USA title.
Tandy won the Miss California USA title in a state pageant held in San Rafael, California on October 15, 2006.She is only the fourth African-American Miss California USA and the first African-American to succeed another African-American titleholder.
Tandy's first "job" in Entertainment was as a stand-in for the "Trista and Ryan" Bachelorette Wedding. Although a fan of the show, Tandy said being a stand-in for the Live wedding was a "terrible" experience and has never worked as a stand-in since.
She temporarily hosted for E! as an online correspondent for E! News Now.
Tandy plays Sophie Moore on Batwoman (2019). She can be seen in national commercials for Wendy's, Boost Mobile, and a movie promotional from the film Shrek The Third.
She appeared in the 2010 movie Unstoppable as one of Denzel Washington's daughters.
She played Lulu Pope on the ABC Family show Jane By Design.
Tandy appeared in Piranha 3DD where she played Ashley Sorby, a girl who meets a gruesome demise.
Tandy also appeared in Trey Songz music video single called Simply Amazing from his new album Chapter V.
When Tandy was casted as "Mystery Girl" on the show, her character was supposedly killed off in the Season 3 premiere, Tattoo. The fans reacted negatively to this as she became likable in that short amount of time.
In March 2017, Tandy revealed that she would not return for the final episodes of Teen Wolf, but she posted a snapshot of herself with a shotgun as a final farewell to the fans.