<P> With his group now armed, Barry and Wendell select thirty people, including Mike and Peggy, forcing them to kneel in a line . He begins executing them with a gunshot to the back of the head . Dany, who has been hiding in the basement, sees what is happening and shuts off the building's lights before Mike and several others can be killed . During this, Dany goes into the elevator shaft with Roberto . </P> <P> Barry and Wendell hunt down the fleeing employees as the voice informs them that only twenty - nine have been killed . The two - hour time limit runs out and Terry, Leota, Peggy and Keith, along with twenty - seven other employees, have their trackers explode, leaving only 16 survivors . They are then informed by the voice that, as a final task, the employee who has killed the most people within an hour will be spared . Barry finds Dany and Roberto in the elevator shaft, but Dany escapes while Roberto is crushed and killed in the elevator shaft . Two employees, Marty (Sean Gunn) and Chet (Abraham Benrubi) collect the un-exploded trackers from the heads of people who have died by other methods, planning to use them to blow up the wall . However, they are killed by Wendell . Leandra kills Wendell, and Barry kills Vince and Dany . He then shoots Leandra, who dies shortly after . Mike and Barry are left as the only two survivors . </P> <P> In a rage, Mike kills Barry with a tape dispenser . The building is then unsealed, as he is the last survivor, and the soldiers escort him to the hangar next door . There, he meets the owner of the voice (Gregg Henry), who introduces himself as a social scientist who believes that discoveries about human nature can only come from placing people in extreme environments . As he and his colleagues begin to question Mike about his emotional and mental state, Mike notices a panel of switches that correspond to the eighty employees . Having planted the trackers that Marty collected on the soldiers and the Voice, he flips every switch except his own . The trackers explode, killing the soldiers and wounding the Voice, before Mike grabs a gun and kills the remaining scientists . The Voice attempts to reason with Mike but Mike kills him . He then leaves the warehouse in a state of shock . The view zooms out to reveal that Mike is one of many sole survivors from similar experiments, being watched by another group through security cameras . A new voice states "end stage one" and "commence stage two ." </P> <Ul> <Li> John Gallagher Jr. as Mike Milch, an employee at Belko Industries </Li> <Li> Tony Goldwyn as Barry Norris, the COO of Belko and an ex-special forces soldier </Li> <Li> Adria Arjona as Leandra Florez, Norris' assistant </Li> <Li> John C. McGinley as Wendell Dukes, a socially awkward top executive </Li> <Li> Melonie Diaz as Dany Wilkins, a new hire at Belko </Li> <Li> Owain Yeoman as Terry Winters </Li> <Li> Sean Gunn as Marty Espenscheid, a cafeteria worker </Li> <Li> Brent Sexton as Vince Agostino, Belko's head of human resources </Li> <Li> Josh Brener as Keith McLure, a tech worker </Li> <Li> David Dastmalchian as Alonso "Lonny" Crane, a maintenance worker under Melks </Li> <Li> David Del Rio as Roberto Jerez </Li> <Li> Gregg Henry as The Voice </Li> <Li> Michael Rooker as Bud Melks, Belko's head of Maintenance </Li> <Li> Rusty Schwimmer as Peggy Displasia, Milch's secretary </Li> <Li> Gail Bean as Leota Hynek, a worker who befriends Wilkins </Li> <Li> James Earl as Evan Smith, Belko's only security guard </Li> <Li> Abraham Benrubi as Chet Valincourt, Espencheid's best friend </Li> <Li> Valentine Miele as Ross Reynolds, a sales representative for Belko </Li> <Li> Stephen Blackehart as Brian Vargas, an interpreter </Li> <Li> Benjamin Byron Davis as Antonio Fowler </Li> <Li> Silvia de Dios as Helena Barton </Li> <Li> Cindy Better as Lorena Checo </Li> <Li> Lorena Tobar as Leezle Freemont, a cafeteria worker . </Li> <Li> Mikaela Hoover as Raziya Memarian, Agostino's assistant </Li> <Li> Maruia Shelton as Agnes Meraz </Li> </Ul>

Who is the voice in the belko experiment