Hmmm … never heard that expression as such, but one plays a ‘hand’ of cards (such as bridge, for example) so possibly the speaker is suggesting that the other person acts deliberately, without haste, and with much planning and thought, rather than acting impulsively. I’d have to know more about the context to hazard any other guess.
’What was your stratagem exactly, Lord Mayfield?’
‘Well,’ Lord Mayfield hesitated. ‘I hadn’t exactly got down to details.’
‘You didn’t discuss it with anyone?’
‘No.’
‘Not even with Mr Carlile?’
‘No.’
Poirot smiled.
‘You prefer …
Hmm… I’d certainly say it is a card-game reference now that I see the passage… I wonder if there is an actual term (‘play a long hand’) from some particular game.
There is an English expression ‘to play one’s cards close to one’s chest’ which, if one is actually playing cards, would suggest being careful not to allow the other players to see your cards but, in general, means being secretive or quiet about one’s thoughts or intentions. It’s funny that Poirot uses the expression we are discussing after questioning Lord Mayfield about other persons to whom he may have revealed his stratagem.
…I only meant that any Russian would understand a 'long hand/arm of KGB’ unambiguously…
Despite now it’s FSB, methods were inherited. In particular, I mean their ‘special operations’ to physical eliminating people, inside and outside the country. And They have a long hand. Long hands of the FSB fixed/will fix him. – quite usual phrases in modern Russian. :?