It all started with a self-pubbed fanfic story called “Master of the Universe”, which—after being re-named, picked up by a small indie publisher and then a larger state-side one—brought erotica out of the bedroom and onto the E train.

“50 Shades” and its sequels broke all kinds of records, spending 32, 29 and 28 weeks on USA Today’s Bestseller List at #1, #2 and #3, before finally ceding this week to make room for No Easy Day: The Firsthand Account of the Mission That Killed Osama Bin Laden by Mark Owen and Kevin Maurer, and A Wanted Man by Lee Child. Note that it took an insider account of the killing of Osama Bin Laden (talk about B/D/S/M!) and a book about why we should never follow an urge to hitchhike ever—to bring the steamy chart-toppers to its knees.

After spending 188 days in the top 100 over at Amazon, the titillating trilogy got bumped down two notches to make room for No Easy Day and Eat to Live: The Amazing Nutrient-Rich Program for Fast and Sustained Weight Loss, Revised Edition, a mass market paperback by Joel Fuhrman.

At the NY Times, “50 Shades” continues to dominate. But Zoo, James Patterson and Michael Ledwidge’s latest thriller, seems to be creeping up fast. Could Zoo do the deed?

Like Ana in “50 Shades”, the trilogy promises not to go easily.  But whatever title does finally end up dominating, it’s a pretty smart bet that the originally-indie bestseller won’t be easily forgotten.