Photo: Brook Rushton/Walt Disney Studios/Everett Collection Rachel McAdams is so much fun in Send Help that she almost makes you forget her character would make a lot more sense played by, say, an Office -era Phyllis Smith. Linda Liddle is an office workhorse who has spent her career trying to get ahead by working late and grinding out quarterly reports through lunch at her desk, only to see the credit stolen by whatever smirking golf buddy has leapfrogged her up the corporate ladder. On top of