George Lucas and the creators of the Silver Age Green Lantern both owe Doc Smith's estate some fat cash. Here's why:
The Lensmen are, to put it simply, a galactic police force armed with starships and most of all, the Lens. The Lens is a large gemlike object set into a wristband that allows the wielder to use telepathy, among other things.
The first book, Triplanetary, is mostly background material and setup for later stories although there are some good space battles.
Things really pick up with the second book, First Lensman. Virgil Samms receives the first Lens from Mentor on Arisia, Rock Kinnison runs for president, and the Galactic Patrol is formed.
The Galactic Patrol has more action than the previous two books put together. Kimbal Kinnison, grandson of Rock, traipses around the galaxy hunting the Boskone pirates, ascending to the next stage of Lensmanship along the way.
The Lensman stories lay the groundwork for lots of science fiction that came afterwards. I'm looking forward to the second volume in the series.