

Release dates sometimes vary between countries. On average a new series has been released every four months. Later series do not have any markings to indicate their contents. In theory, this will allow customers to continue identifying the figure enclosed within.

Lego has eliminated the figurine-specific bar codes on all Series 3 and 4 packets and replaced them with a braille-like system of dots embossed in the lower seal of the bag. There are also apps for both iPhone and Android devices that utilize these bar codes. This has allowed customers to identify individual figures within the packet, significantly decreasing the amount of money and effort required to obtain a complete collection, and eliminates the possibility of unintentionally receiving duplicates. Despite attempts to obfuscate the contents of these packets, the bags of Series 1 and 2 have a second figurine-specific bar code on the rear of the packet, next to the EAN/UPC product bar code (which is unique to each series). Purchases from many retailers make no guarantees regarding the contents of a particular packet. While considered a novel approach by some, it has raised controversy amongst enthusiasts and collectors, increasing the amount of difficulty in obtaining a complete collection. The figures are sold individually in sealed, unmarked packets, giving customers a random chance at obtaining any particular figurine.

The series consists of a number of individually themed collectible Lego minifigures based on movies, sports, history, and popular culture.
