Three Heroes

Historical: John Sanders' Nicholas Pym, like a 17th century James Bond.

Contemporary (at the time of writing): Ian Fleming's James Bond.

Futuristic: Poul Anderson's Dominic Flandry, like an interstellar James Bond, although the first Flandry story predates the first Bond novel.

The order of the creation of these characters is the reverse of their fictional chronological order.

A meeting of buccaneers on Tortuga, attended by Pym, parallels Goldfinger's "Hoods' Congress," attended by Bond. The Mafia and SMERSH are represented at the Hoods' Congress. Real historical buccaneers attend the meeting in Tortuga. In both cases, a man is murdered leaving the meeting.

In such series, a heroine is usually a single-volume character to be disposed of between volumes. See The Structure Of A Series: Ian Fleming. (Scroll down to the section on "Heroines.")

In the Pym series:

the heroine of Volume I has died in childbirth before the beginning of Volume II;

despite her association with Pym, the heroine of Volume II remains a Royalist and Pym shoots her when she tries to assassinate Cromwell;

if I remember right, Pym meets someone at the end of Volume III whom he marries in Volume IV;

Volume V, which I have not read, is a flashback to a time earlier in Pym's career so we already know that its heroine, if any, will not be around later.