I was watching the most recent season of Doctor Who on DVD and it struck me that Rory very much resembled a live-action Shaggy (much more than Matthew Lillard did in those two mediocre Scooby movies). That was all it took for the idea of a Scooby/Doctor Who mashup to pop into my head.
I found the classic Scooby Doo "running characters" title screen online and started substituting Who characters for the Scooby ones. Obviously the Doctor had to be Fred. Amy worked out perfectly as Daphne. As I mentioned earlier, Rory makes a perfect Shaggy. River Song's not really all that Velma-like, but she'll have to do. I needed a Scooby, so who better to fill that part than the only dog in the Whoniverse-- good old K-9? Then all that was left was to substitute a Cyberman for the Creeper. It worked out much better than I expected. Why, it's almost as if the Who producers planned it that way.
I tried to match the Hanna Barbera animated look as much as possible, so it's a little different from my usual style. I think this was the first time I've ever drawn a Cyberman. They're tough to draw. Lots of angles and fussy little lines.
Before anyone says anything, I know that Amy didn't wear that outfit in The Pandorica Opens, but the Scooby girls both wore skirts, and I wanted at least one of the females here to be wearing one as well, so I fudged Amy's outfit a bit. Technically Rory should be in his Roman Legionnaire duds too, but I nixed that idea because I wanted to play up his resemblance to Shaggy. And of course K-9's never been in any Matt Smith episodes, but I needed a dog, so... chalk it up to Artistic License.
The text was hand drawn, based on the original Scooby lettering. Odd that the original title is actually a question, but there's an exclamation point at the end instead of a question mark.
Drawn in Photoshop on the graphic tablet.
Here's the original Scooby Doo title card.