Also, one-man band. A person who does or manages just about everything, as in This department is a one-man show—the chairman runs it all, or John conducts the interviews, writes the articles, solicits ads, deals with the printer—he's a one-man band. This idiom alludes to the actor or artist responsible for the entire performance or exhibit, or the musician who plays every instrument in the group. [First half of 1900s]
Examples from the Web for one-man show
Historical Examples of one-man show
I shall have a one-man-show next season; and then there will be no more money troubles.
Of course I shall sell them next year fast enough, after my one-man-show; but while the grass grows the steed starves.