Let's start with the Flintstones area. Once you have the Doctor and his TARDIS unlocked, head back to level two in the game. It's the Simpsons' one.
Play all the way through the level until you beat President Business from "The LEGO Movie."
You'll then be placed in Mr. Burns' office.
Before you do anything else, turn your attention to a hacking device on the left.
next slide will load in 15 secondsSkip AdSkip AdThe first time you were here, you probably couldn't access it. You needed a Lego character with the ability to "hack." Thankfully, the Doctor can do that!
You'll be transported into a Pac-Man-like mini-game where you need to hit three switches to win.
Once you're back, you'll get a pile of Legos.
Put them together and you'll have a travel pad for the TARDIS.
Then break out the Doctor's time machine, place it on the launch pad, and you're off!
next slide will load in 15 secondsSkip AdSkip AdSomehow, even though they didn't get into the TARDIS, everyone manages to show up at the prehistoric Flintstones' home.
There are a lot of nods to the '60s show. The Flintstone car sits in the garage waiting to come to life.
If you conjure up Scooby Doo (another Hanna-Barbera character), he'll dig up a T-bone steak which you can jump on afterwards as a trampoline.
Who knew steak was so bouncy?
next slide will load in 15 secondsSkip AdSkip AdLying atop the roof you'll find a red guitar, which may hint that you may not be the only time travelers to have visited.
Yes, you can head inside, too!
Take a look for yourself.
There are a few hidden items scattered across the two rooms.
The best may be this record player in the corner, which you can actually turn on.
next slide will load in 15 secondsSkip AdSkip AdThe Jetsons' hidden area is easier to get to — but you need the Homer expansion pack to access it.
Head into the level "Mysterious Voyage of Homer" which comes with the Simpsons character.
When you come across a double decker London bus, break it apart.
Then rebuild it to make a TARDIS travel pod appear.
Enter the Tardis and you'll be swept away to Orbit City, the futuristic home of the Jetsons.
next slide will load in 15 secondsSkip AdSkip AdSimilar to the Flintstones' area there are a few more of those Slushee cups to pick up.
Take a look at the scenery and you'll see the familiar city backdrop.
It's a much smaller area than the Flintstones one.
But there is a mini-game to play and some serious Lego dough to collect.
Those are just two hidden locations in the game. There are probably even more that haven't been found yet. Happy searching!