Three Organizations

There are three versions of SMERSH:

a real WWII counter-espionage organization;

a fictional organization introduced in Ian Fleming's first James Bond novel;

an organization described in a dodgy dossier that was handed in to The Sunday Times and that influenced Fleming's presentation of the fictional organization in his fifth James Bond novel.

(This explains, if it does not excuse, Fleming's claim, in an initialed author's note, that From Russia, With Love presents an accurate account of SMERSH.)

There are perhaps three versions of SPECTRE:

a fictional organization in a screen treatment by Ian Fleming, Kevin McClory and Jack Whittingham;

a fictional organization introduced in Fleming's novelization of the screen treatment;

a larger fictional organization introduced in the first Sean Connery James Bond film.

There are two accounts of Thrush:

it is introduced in The Man From UNCLE TV series;

it is creatively elaborated in David McDaniel's original UNCLE novels.

Since Fleming had planned a James Bond TV series and also had some input into the UNCLE TV series, there is a direct line of descent from SMERSH through SPECTRE to Thrush. Furthermore, former members of the disbanded SMERSH joined SPECTRE and former members of the WWII SMERSH might well have joined Thrush.