She had two releases in 1996, though neither created as big an impression as had her debut. In the actioner "Maximum Risk," Henstridge portrayed the girlfriend of Jean-Claude Van Damme's dead twin. Later that year, in "Adrenaline: Fear the Rush," she co-starred with Christopher Lambert, as futuristic cops tracking a serial killer. Henstridge went on to co-star with Robert Sean Leonard in "StandOff" (1998), a drama inspired by recent FBI/militia stand-offs and played a clone of the alien in the inevitable sequel "Species II" (also 1998).
Although several of her features ended up direct-to-cable, Henstridge did enjoy a pivotal supporting role in "Bounce" (2000), playing the attractive woman who causes Ben Affleck to switch plane tickets with another man who is then killed when the flight crashes. She scored in a vulnerable role as mobster Bruce Willis' unhappy wife who finds love with neurotic dentist Matthew Perry in the hit comedy "The Whole Nine Yards" (2000); reprising the role for the 2004 sequel "The Whole Ten Yards." The actress then undertook perhaps her most challenging role to date – replacing an injured Courtney Love just before shooting began on the sci-fi thriller, "Ghosts of Mars" (2001). Appearing in virtually every scene of the film, she gave a heroic turn as a futuristic police officer who must join forces with hardened criminals to battle the titular spirits.
In 2002, Henstridge portrayed the character of Cassie in the NBC action series, "She Spies" (NBC), which co-starred Kristen Miller and Natasha Williams. She also delivered a strong, sexy performance as Judith Campbell Exner (lover of both President John F. Kennedy and his nemesis, mob boss Sam Giancana) in the otherwise standard Showtime biopic, "Power and Beauty" (2002), before appearing opposite James Brolin in the Lifetime telepic, "Widow on the Hill" (2005). Continuing a successful run on the small screen, she took on a recurring role on the political drama "Commander In Chief" (ABC, 2005 - ) as Jayne Murray, assistant to the Speaker of the House (Donald Sutherland).