Film
Lockhart's first film role was playing Dora in the 1973 Western Jory. That same year, she appeared in the critically acclaimed Hallmark Hall of Fame episode Lisa, Bright and Dark, alongside Kay Lenz, Anne Baxter, and John Forsythe. She then appeared in the films Slashed Dreams (1975) and Joyride (1977), with Robert Carradine and Melanie Griffith. She played the young Eunice St. Clair in the 1986 horror film Troll, with her mother playing the older version of her character. Her other film credits include Just Tell Me You Love Me (1978), Hambone and Hillie (1983) opposite Lillian Gish, Young Warriors (1983), The Oasis (1984), The Serpent Warriors (1985), Dark Tower (1989), Big Bad John (1990), Bug Buster (1998), A Dog's Tale (1999), Daybreak (2000), Cahoots (2001), Hollywood, It's a Dog's Life (2004), ExTerminators (2009), and Dakota's Summer (2014).
Though Lockhart herself claims no recollection of being approached, she was reportedly John Carpenter's first choice to play the role of main character Laurie Strode in Halloween (1978). Other commitments kept her from doing so, and the part was played by Jamie Lee Curtis in the original and 6 sequels.
