The Emerald City Lego set for Lego Dimensions video game at the E3 Electronic Entertainment Expo in Los Angeles on June 18, 2015

Warner Bros this week showed off Lego Dimensions, its latest videogame that mixes real-life toy play with digital gaming.

Unveiled at the Electronic Entertainment Expo (E3) trade gathering in Los Angeles, the new game comprises Lego figurines from a range of film franchises including "Batman" and "Back to the Future."

Once a gamer places a toy on a special Lego plastic pedestal, it immediately comes to life as a digital character in a videogame.

The gaming system, which will be available later this year, is the latest in a growing category of physical-to-virtual games known as "toys to life."

Such games have proved popular in recent years with offerings such as "Skylanders" and "Disney Infinity."

In the fall, Disney will launch a toys-to-life videogame based on the "Star Wars" franchise.