Motifs in the James Bond film series the degree to which Bond girls are pivotal to propelling the plot forward varies from one film to the next. Five of the Bond girls are "bad" girls (or at least working for the villain) who turn "good" (or switch sides) usually due to Bond's influence. Bond has fallen in love with only Tracy di Vicenzo in "On Her Majesty's Secret Service" and Vesper Lynd in "Casino Royale", but both of them die at or near the end of the respective films. Roald Dahl, a screenwriter of "You Only Live Twice", said he was given a formula to work to
Vesper Lynd David Niven), now in the position of M at MI6, uses a discount for her past due taxes to bribe her into becoming another 007 agent, and to recruit baccarat expert Evelyn Tremble (Peter Sellers) into stopping Le Chiffre (played by Orson Welles). Vesper and Tremble have an affair during which she eliminates an enemy agent sent to seduce Tremble ("Miss Goodthighs"). Ultimately, however, she betrays Tremble to Le Chiffre and SMERSH, declaring to Tremble, "Never trust a rich spy" before killing him with a machine gun hidden inside a bagpipe. She presumably does this for the same reason she