HBO has just confirmed that Rachel McAdams will join the cast of "True Detective" season 2. Rachel McAdams, Taylor Kitsch & Kelly Reilly join Colin Farrell & Vince Vaughn in season 2 of @HBO's #TrueDetective: http://t.co/ZUSwJVFJIw — HBO PR (@HBOPR) November 24, 2014 The actress will star alongside previously announced castmembers Vince Vaughn and Colin Farrell.