Born on July 3, 1970, in Orangeburg, South Carolina, Smith debuted on the big screen at 11, as a dancer, in mogul Ray Stark's multimillion-dollar production of Annie (1982). A bit part in Michael Tuchner's acclaimed telemovie Not My Kid (1985) followed, at the age of fourteen; the picture drew solid Nielsen ratings and favorable critical responses, but Smith's only amounted to a bit part. She maintained greater visibility in the late eighties, with two significant roles: Rhonda Altobello in Carl Reiner's 1987 Mark Harmon-starrer Summer School. While most critics dismissed the film, it charmed a handful of others (such as Kevin Thomas and Rita Kempley) and did outstanding box office for a programmer, grossing several times its original budget. The very same could be said of Chuck Russell's 1988 remake The Blob, and then some: in addition to delighting nostalgia-hungry moviegoers (and some critics), it purportedly acquired a loyal following, becoming - in time - something of a cult film.

Over the nineties and into the 2000s, Smith evinced a predilection for slightly deeper and more intelligent fare, but kept a somewhat low onscreen profile for several years, usually (though not always) with bit parts in lower budget indie dramas. Smith also appears in director Paul Quinn's Never Get Outta the Boat, which dramatizes the lives of several recovering addicts. She landed a regular role as Linda, a not-so-bright nurse's aide, on the 1998 CBS sitcom Becker, starring Ted Danson, and stuck with the series until it wrapped in 2004.

When Smith's horror film quotient skyrocketed in the early 2000s (with the Saw role) it temporarily eclipsed her involvement in more substantial fare, even as her screen activity per se crescendoed. In the vein of earlier slasher film franchises, the initial Saw entry and its sequels did exemplary box office and obtained a rabid following; surprisingly, the pictures drew a favorable response in some critical quarters, as well.