Before he became an internationally acclaimed theatermaker, Robert Lepage came from "887."

The nimble actor, director and writer spent much of his youth in an apartment building at 887 Murray Avenue in Quebec City. In the enthralling and witty solo show "887," on stage at Walker Art Center through Saturday, his childhood home is represented by a dollhouse-like structure, about 7 feet tall, 3 feet wide and 10 feet deep, which Lepage keeps turning and manipulating to show new aspects of life there.

As he points to individual apartments, doll-sized videos appear in each window, revealing residents vacuuming floors, hanging laundry or jumping on beds. Introducing us to his former neighbors, Lepage is like Jimmy Stewart in "Rear Window," gesturing with his binoculars as he and Grace Kelly peep into the lives of the people across his courtyard.

Those 3-D videos are just the first demonstration of Lepage's technical wizardry (you'd swear he found tiny actors to participate in the show with him). By the end of the two-hour show (with no intermission) Lepage has employed live video shot with his cellphone, shadow puppets, remote-controlled cars, mime and — thanks to an invisible crew of nine that takes a much-deserved bow at the end — a set that is constantly reconfiguring itself in new and more magical ways.

Lepage's subject is himself, although "887" is too generous to feel ego-driven. It's more like he's using himself as an example of how we delve into our memories to solve the mystery of who we are.

"887" really presents us three Roberts: the effortless charmer who dazzles us with funny stories of his youth; the petty and vain blowhard who shows up when Lepage enlists a friend to help him learn a poem he's having trouble memorizing, and the magnetic performer who appears, seemingly out of nowhere, to deliver that poem — Michele Lalonde's fiery "Speak White" — with precision and fervor.

So, who's the real Lepage? Like many of us, he's a lot like his dad. He's also like that apartment building, whose residents' woes we learn more about: The exterior is not the whole story. Increasingly, Lepage turns to memories of his father, who was remote from the family because he worked so hard to support them, and to the realization that he knew little about his father's internal life, much of it experienced in the front seat of a taxicab. But maybe Lepage's memories can help him understand his late father now.

By the end of "887," theater, memory and imagination converge as Lepage sits silently in his father's cab. It's a memory he could not possibly have — he wasn't there — but it's also a reminder that, like Lepage, we struggle to remember the past because we know that if we don't, we will not be remembered ourselves.