Looking for another reason to see the Finding Nemo 3D rerelease? Discover Partysaurus, the new Toy Story short set to precede Marlin and Dory's return, starring the one and only Rex. 

Wallace Shawn returns to play your favourite plastic dinosaur as he goes for a soapy swim in his new owner's bathtub, with Bonnie introducing him to a whole horde of rubber duckies. 

In the picture above, you can see Bonnie in full flow, bubbled up and ready to take Rex on an adventure. You can also see a number of little hat-tips to other Pixar movies - how many can you spot? To get you started, take a look at the loo seat...

Click on either picture to see a bigger version over on EW.com

Here in this disco-themed still, there's a element of ravers' fantasy to Bonnie's bathtub funtimes, with Rex looking about as silly as he's ever looked, ever.

In the director's chair is Mark Walsh, who has previously helped animate the likes of Ratatouille, The Incredibles and, as you'd expect from something this aquatic, Finding Nemo.

American Toy Story (and Finding Nemo) fans can look forward to watching this short (and Finding Nemo 3D) when Andrew Stanton's masterpiece hits US cinemas this September. British Rex aficionados will have to wait until some point mid-2013, however. Sorry about that, chaps.