Former congressman Robert Mrazek on the set of “The Congressman.” (Photo courtesy of Thomas Hurd.” )

At 70, former Rep. Bob Mrazek has figured out what he wants to be when he grows up.

It only took a stint in the Navy, a decade in Congress representing Long Island, and writing eight books to figure out: he wants to be a film director. The New York Democrat is coming to Washington next week to screen his directorial debut, an upcoming small-budget movie he also wrote called “The Congressman” (they say to stick with what you know, right?).

Mrazek says directing was a childhood ambition, and he even began attending the London Film School in 1968 when the assassinations of Martin Luther King, Jr., and Robert Kennedy pulled him back home, where he began working for an anti-war senator. “The detour took about 30 years to correct,” he says.

“The Congressman,”  a nonpartisan political comedy about a burned-out lawmaker, has an impressive cast for an art-house flick: Treat Williams stars as the titular lawmaker, George Hamilton plays a smarmy lobbyist (how has that not happened before?), and “House of Cards” alums Jayne Atkinson and Elizabeth Marvel are in supporting roles.

Here’s hoping Mrazek doesn’t get bounced from his own movie showing at the Motion Picture Association of America next week — the late Jack Valenti, who headed the MPAA  when Mrazek was in Congress in the 1980s, banned him from the organization’s premises. Mrazek had written legislation, over Valenti’s strong objections, creating the National Film Registry that protects “significant” movies from alteration.

And Hamilton, who Mrazek hopes will attend the April 14 event, also has an old Beltway beef.  The actor, now 76, briefly dated Lynda Bird Johnson, a courtship that prompted LBJ to order both Supreme Court Justice Abe Fortas  and the FBI to dig up dirt on the young actor. “It kind of soured him on Washington,” Mrazek says.