Del Toro got Valve's permission to use GlaDOS' voice in Pacific Rim
The presence of Ellen McLain's sultry, robotic trills in the Pacific Rim trailer above filled us with much, much joy when we first saw it last December, but we couldn't help but feel like director Guillermo del Toro wasn't being entirely original. Furthermore, we wondered how Valve would feel about such flagrant counterfeiting; we know it doesn't own Ellen McLain's voice or anything, but come on.
None of that is actually an issue, as it turns out, since del Toro actually obtained permission from Valve to use GlaDOS' voice in the film, according to the Toronto Sun. "I wanted very much to have her, because I'm a big Portal fan," del Toro said. "But just as a wink. She's not cake-obsessed."
McLain's vocal work in the actual film will be run through fewer GlaDOS-inducing voice filters in the final film, del Toro says, but he wanted her voice to be completely recognizable in the trailer. It's also worth noting that there's no actual crossover between Valve's Portal/Half Life universe and Pacific Rim's, even though Pacific Rim is a movie about universes crossing over.
