The most dynamic character is Dick. He is the one with ideas; he is the one who makes things happen. Arguably the central event of the Clutter murders is really down to him, even if it’s Perry who instigates the actual killing. But the whole plan of robbing the Clutters is Dick’s, after the idea is put into his head by his former cellmate Floyd Wells. Then, when they don’t get the money that they expected from the Clutters, he goes on concocting various schemes to make money, selling gear, passing bad cheques, travelling about the country. Even their final capture comes about when Dick takes the huge risk of returning to Kansas.
Although Perry also has ideas – mainly impractical schemes of diving for buried gold off the Mexican coast – it is Dick who has the drive and energy to actually do things. Perry generally just goes along with him, as he says subsequently:
The mood I was in, I just let myself be carried along.
Perry thus appears somewhat passive, but in allowing himself to be swept along by Dick, he helps create the circumstances for the brutal murder. Although Dick sets the whole thing up, it seems he would never actually have had the nerve to go through with murder, but Perry does. Perry, on his side, would probably never have planned such an undertaking by himself. Together, however, the two men make for a lethal combination.