He's the guy on the $100 bill, the inveterate tinkerer renowned for flying a kite during a rainstorm, the man who came up with the idea for daylight-saving time, the 18th-century world traveler who made the first comprehensive map of the Gulf Stream, the only president of the United States - to borrow a line from the Firesign Theater - who was never president of the United States.

Or to put it another way: Benjamin Frank- lin was the first truly Renaissance figure in U.S. history, an intellectual genius whose working-class roots made him an early champion of the democratic ideals on which this country would eventually be founded. As a statesman and diplomat, he - more than Washington, more than Jefferson - may have been the key figure in this nation's birth.

Tonight and tomorrow on PBS, Franklin gets a TV biography befitting his stature. Benjamin Franklin not only weaves a compelling tale, in tracking this tradesman's son from the back streets of Boston to the royal courts of Paris to Philadelphia's Independence Hall, but it entertains as well, thanks to an engaging mix of scholarship and drama that fleshes out Franklin's story without cheapening it.

An amazing feat, considering that much of the 3 1/2 -hour production (two hours tonight, 1 1/2 tomorrow) consists of actors, portraying Franklin and his contemporaries, addressing the camera directly. Such re-enactments often prove the bane of historical documentaries, which are usually better served when their stories are told through pictures, erudite talking heads and off-screen narrators. But filmmakers Ellen Hovde, Muffie Meyer and Ronald Blumer never allow the actors to dominate the story or to call attention to themselves. And it helps that the cast is accomplished and/or talented enough - especially Tony Award-winner Richard Easton as the older Franklin - to serve rather than be the story.

It also helps, of course, to have a compelling story to tell in the first place.

The flashpoints of Franklin's life - Poor Richard's Almanac, electricity, the Revolution, autobiography - have become part of American folklore, but the finer details tend to be forgotten. It's in those details that the true measure of the man is found.

Part 1, "Let the Experiment be Made" (9-10 tonight), introduces Benjamin, the 15th son of Boston candle and soap maker Josiah Franklin, as the product of a world where, only 15 years before his birth in 1706, women were accused of being witches and were being burned at the stake in nearby Salem, Mass. It was a world in which superstition reigned over science and men were born to certain stations in life, with little hope of advancing.

For much of his life, Franklin would work to change both of those fatalistic concepts, helping to usher in an age of reason and of at least intellectual equality. He was, says Robert Middlekauf of the University of California at Berkeley, "a very powerful mind with a very powerful curiosity, immense gifts and considerable flaws."

But he never viewed himself as better than his times; one of his early heroes was the famed Puritan preacher, Cotton Mather, who once vowed never "to enter or leave a room without doing some good in it" - words Franklin lived by.

The first hour details how Franklin establishes his reputation, first as a printer (one of the most successful in the Colonies), and later as a scientist. He was among the first - perhaps the first - to understand electricity, and suspect that its power could be harnessed for good. His work in the sciences made him world famous.

Part 2 (10-11 tonight), "The Making of a Revolutionary," examines how Franklin went from being intensely proud of his British heritage and citizenship to leading the Colonies' struggle to be free. "Retired" at age 42, thanks to a fortune made as a printer and writer (his Poor Richard's Almanac included such invaluable bon mots as "Love your neighbor, but don't pull down your hedge"), Franklin turned against the Crown only after being humiliated before a British court.

Ironically, he was attempting to make peace between Britain and America when his efforts backfired and he fell out of favor. He never forgot, or forgave, how quickly the British turned on him. In July 1776, his signature would appear on the Declaration of Independence - a document he helped draft.

Part 3, "The Chess Master" (9-10:30 p.m. tomorrow) traces Franklin's career as a diplomat - he almost single-handedly persuaded France to ally itself with the Colonies during the Revolution - and statesman, helping to draft the Constitution.

Benjamin Franklin gives its subject the treatment he deserves. Keeping in mind all Franklin did during his lifetime, that's no small accomplishment.

Premiere

What: Benjamin Franklin

When: 9 to 11 tonight and 9 to 10:30 tomorrow

Where: MPT (Channels 22 and 67) and WETA (Channel 26

In brief: A compelling story, well told