Ready Player One author and screenwriter Ernest Cline has told RTÉ Entertainment that Steven Spielberg does not know about all the 'Easter Eggs' that have been hidden in the director's big screen version of Cline's best-selling book.

The gaming adventure, which opens in cinemas on Thursday, is chock full of nods and winks to films, music, arcade classics and iconic characters, with fans of Spielberg and Cline's book set to have their work cut out to find all the references, hidden and otherwise.

Fans won't know where to look with all the film references

When asked if a definitive list had been drawn up of all the references onscreen, Cline replied: "There is for the novel - people have created them - but the movie, not yet. I imagine there will be once the Blu-ray comes out and people can go frame by frame."

Yes, that car has a cameo

"Even Steven and I aren't aware of all the Easter Eggs in the film because the special effects artists at ILM (Industrial Light & Magic) and Digital Domain both snuck their own things in the background, knowing that we wouldn't spot them!" 

You'll be looking for Easter Eggs in every scene

"I know Steven in his last run-through spotted a Gremlin that he didn't even know was in the movie!" laughed Cline.

Steven Spielberg hits the road for Ready Player One

"No one has made a list yet, but I imagine probably around August it will be forthcoming."

Ready Player One opens in cinemas on Thursday March 29.

Read our review here.