They call them "Buddy Flics." Two guys are placed by the screenwriter into a partnership that becomes the primary thread that carries the action of the movie. Think Abbott and Costello, Laurel and Hardy, Gibson and Glover (Lethal Weapon), Dean Martin and Jerry Lewis, and Matthau and Lemmon (Odd Couple) amongst dozens of others. These were magical partnerships that would propel the couple through adventures and escapades (often quite messy and later bloody – but almost always humorous). It is the quintessential Hollywood vehicle for storytelling.
Concurrent to the male-male story, the mixed Buddy Film emerged with couples such as Nick and Nora Charles (Thin Man series and other films), Humphrey Bogart and Lauren Bacall (not necessarily a series but a couple that sparked sexual energy and box office dollars), and of course Ginger Rogers and Fred Astaire. The sexual nuance could now be employed with, in most cases, the woman equal to the man (and often smarter). And who can forget Mickey and Minnie.
Thelma and Louise changed the roles to a darker side, two women out for a good time that goes bad. While the genre could be two women it has to have two strong actors and a great story to pull it off. There not many to choose from.
In the modern era, literature has used this vehicle to carry a story since Don Quixote and Sancho Panza rode across the Spanish Plain. Sir Arthur Conan Doyle's Sherlock Holmes and Dr. Watson, Dashiell Hammett used it in his Thin Man series (books and screenplays), and Steinbeck's Of Mice and Men.
The goal of today's mystery and thriller writer is to use this archetype to inject conflict, humor, and movement to the story. It is seldom used in the first person telling of the story, the "I said and then you responded," can be confusing. The Lone Wolf character seldom needs a partner – Jack Reacher works alone (in Lee Child's stories Reacher "bumps" into characters for the action). The greatest purpose of the Buddy Book is to draw out the two main characters in ways that the action of the story can't. In David Baldacci's King and Maxwell series (six books and counting) we have an older man (ex-Secret Service) and a younger woman teamed as detectives. They bitch and moan at each other, name call, and otherwise act like any married couple except they aren't. The action of the story is paired with a soft sexual tension that pervades their conversations – the "will they or won’t they" is placed in the mind of the reader as the two act to save the president of the United States, oh-hum (actually a great read).
The writer can structure their books with a main character and subordinates (I call it the office model – boss and minions), lone wolf with casual walk-on/die off guests, Buddy (man-man, man-woman, man/woman-pet (ouch), and woman-woman), or in the case of some very strange works of fiction a robot or car (think Stephen King). All character structures work but it is often found that with a partnership the writer can further develop and deepen the characters. The reader may more easily identify with one or the other of the leads, especially in a man-woman structure. It also allows for a broader relationship to the marketplace – guys for guys and gals for gals – or the switch to guys for the sexy successful gal and gals for sexy unstoppable hunk of a guy. Just saying.
I've found in my Sharon O'Mara and Kevin Bryan stories my two characters just want to bust out in each book. Each wants top billing (at least in my head) and I have to continually push Kevin back since it is Sharon's chronicles. I try to balance them with the number of words each is entitled to, and I have found that Sharon needs to learn to share. For some buddies sharing is tough.
Every writer I've met that writes buddies is faced with the same conundrum: Do I keep the same model or will I, in the next book, switch the roles of the partners? More than once, such as in the Stephen Coonts Jake Grafton stories, Tommy Carmellini (the quasi-partner) wants to tell his story too. It is an all to often problem, think Rhoda from Mary Tyler Moore and Frasier from Cheers (okay a stretch but you get my drift). But when you spin-off one buddy who becomes their buddy? Just asking.
More later . . . . . . . .