A book speculates that one motivation for the Heydrich assassination may have been an effort to protect Canaris, a high ranking German officer who was a double agent.
Just got to that part in the Canaris book, and while author concludes that Operation Anthropoid was an SOE (Special Operations Executive- military intelligence/sabotage), not SIS (i.e. MI-6 aka the James Bond folks)inspired plan; he does mention that when the local Czech resistance requested that Anthropoid be cancelled, Sir Stuart Menzies (aka "C" the head os SIS/MI-6)got involved in moving the plan forward. For what it's worth, the excellent (vintage B&W- and on youtube w/ English subtitles) Czech movie "Attentat" describing these events, features the Canaris/Heydrich rivalry.