In the book it is obvious, but it is supposed to be. M calls Bond into the situation because Drax is a national hero, but it is clear that he cheats at cards, and the owner of the club where Drax plays (Blades?) is afraid that a scandal when the cheating is revealed will hurt the Moonraker project.
So M brings in Bond to spot how Drax is cheating (the Shiner mentioned previously, where Drax can see what cards he is dealing reflected in the silver cigarette case in front of him). Then Bond suggests the rigged deal to show Drax that they know he is cheating, and to give him a sharp and expensive lesson so he doesn’t do it again.
In the book, when Drax realizes he has lost, he starts to say “You’re a che-” and the chairman cuts him off instantly and tells him that he has to put any accusations of cheating into writing and send them to the committee in charge. The implication is that, if Drax does that, they will reveal that Drax has been cheating and have him socially ruined.
I have never played bridge, and I didn’t even try to understand the details of the rigged deal that Bond uses.
IIRC, in the book, it was indeed obvious. The set up is that the club leadership was convinced that Drax was cheating, but hadn’t caught him in the act, so they ask Bond to sit in as a ringer. He spots how Drax is cheating and (with the club’s implicit permission) rigs the deck.
After the rigged hand all goes down, Drax is sitting there realizing he’s been set up. Just before he can say anything the club manager comes by and pointedly tells Drax that he hopes there’s not going to be anything so unpleasant as an accusation of cheating, is there? Which is their way of telling Drax that his cheating gig is up and, since he’s just lost back the money he won cheating, the club is willing to keep everything quiet, but if Drax makes a stink about this hand, he’ll be exposed and socially disgraced. Drax gets the message and angrily pays (and plots revenge on Bond, triggering the main plot of the book).
Edit: Curse you Shodan! My minions will take revenge upon you!
Of course, any idiot can make a Grand with a whopping 8 HCPs - here’s how to do it with five:
South holds five Spades to the Ace and eight bus-tickets in Clubs
North holds six Spades to the Knave and seven irrelevant red cards
The remaining Spades break 1-1 and the Clubs break 3-2; neither opponent has a red-suit void.
Whatever is led, declarer wins the trick in hand or dummy, draws trumps in one round and cross-ruffs for six rounds finishing in hand. His five remaining Clubs are now good.
Bond is cut a check for the £15,000, so I assume he and M each got £15,000 and therefore Drax and Meyer each owed £15,000, but I don’t know if the implication was Drax took Meyer’s losses for the disastrous last hand, or the evening. I’ve always assumed the evening, since his cheating is why Meyer lost so much money ultimately.