HARTFORD, Conn. (AP) - By day, Jon Berk is a mild-mannered civil attorney in Connecticut.
But by night (well, really during most of his spare time for the past 45 years) he is known by some as a comic book-collecting super hero.
Berk's collection of more than 18,000 books and 300 pieces of comic-book art goes on display March 11 at the Metropolis Gallery in New York City. He will then sell it off during an online auction at ComicConnect.com that begins May 15.
"The time is just right to move them along and let someone else experience them," said Berk, 66.
The collection includes rare copies of the 1938 Action Comics No. 1, in which Superman makes his first appearance; the 1939 book Detective Comics No. 27, which features the first appearance of Batman; rare Spider-Man and Captain America books and several pieces of art by noted comic-book artist Lou Fine.
Vincent Zurzolo, the chief operating officer of ComicConnect and Metropolis Collectibles, said Berk's collection is one of the most important in the world because of its breadth and the number of rare books dating back to the mid-1930s.
"As I've been going through this collection, I've seen books for the first time, books I've never seen before," Zurzolo said. "That's incredible, considering we're the largest buyer and seller of vintage comic books in the world. Many of these copies are the best known to exist in the world."
Berk said he expects the collection will sell for hundreds of thousands of dollars, if not more.
But he said his collecting was never about the money or investing.
He said he fell in love with the serial plot lines in the books as a boy. He then began collecting them while in law school at Boston University, enjoying the hunt for a particular rare book, researching the story behind it and documenting what he refers to as a "unique American mythology."
He said friends were always shocked when he would take the books out of their Mylar sleeves and let them thumb through them.
"What good is a work of art if you never look at it?" he said. "What good is a comic book if you can't open it up, see how it feels and, yes, smells?"
Up until a month ago, he was still buying the latest Spider-Man comic books (his favorite), just for fun.
"I figured if I was going to have Spider-Man No. 1, I was going to have Spider-Man 700," he said. "And I will keep some Spider-Man books, some old books, for sentimental reasons."
Copyright 2017 The Associated Press.