A retired Minneapolis bus driver who died in a fire last year had a passion for comic books. The fire that took his life started in the kitchen, but a back bedroom filled with more than 20,000 comics was spared. It was just recently that the surviving family members realized the collection was worth about $1 million.

According to the Star Tribune, Gary Dahlberg started collecting comic books in the 1960s and would spend lots of time in comic stores or at comic book conventions. He also collected Star Trek–related items of all sorts, and liked having some of his figurines in the refrigerator to have something to look at when he opened the door.

Living a humble life, he sold two comics before his death – one to buy a computer so he could catalog his collection, and one to help pay off his home. Some family members questioned the value of his hobby, but now that the collection has been appraised, the Star Tribune says the hobby is more valuable than they ever could have imagined:

2,500 to 3,000 of Dahlberg's 20,000 comic-book collection would end up "easily" worth more than $1 million. "Maybe closer to $2 million," said Ed Jaster, senior vice president of Heritage Auctions.

Some of the comics of note in the collection are from 1963 : The Amazing Spider-Man No. 1 and No. 2. The No. 2 issue is one of only five known copies. The company hired to appraise and certify the collection will sell the comics in the coming year. While 3,000 of the comics are valuable, the majority will only be worth around twice the cover price.

So, collectors, look for comics from the Gary Dahlberg Collection.