How it unfolded
The Lakers, leading the series 2-1, played their second straight game in Boston. LA once led by double digits, but the Celtics erased it in the fourth quarter. With 29 seconds left, Larry Bird hit a three to put Boston up 106-104. Kareem Abdul-Jabbar made just one of two free throws to cut it to one, and in the scramble after the missed second attempt the ball caromed off a Celtic and out of bounds, letting the Lakers keep possession. Magic Johnson caught the ball on the left baseline, drove between Robert Parish and Kevin McHale, and lofted a right-handed hook shot — what he later called his "junior, junior sky hook" — that fell through with two seconds left, making it 107-106. Boston still had time, and Bird's three from the left corner just rimmed out. The win pushed the Lakers ahead 3-1 in the series, which they closed out in Game 6, and Magic won both regular-season and Finals MVP that year.
Why it still matters
This is the single most-cited moment in the eight-year Magic-Bird rivalry, and the point at which the 1980s Lakers cemented their edge over the Celtics. That the point guard, not the center, carried forward the sky hook that had symbolized the franchise under Abdul-Jabbar — and that the shot came inside Boston Garden itself — completes the story. The Lakers repeated as champions the following year and closed out the 1980s with five titles.