Last Broadcast interviewed The Sarah Jane Adventures co-producer Phil Ford to talk all about the series. An extract is below, read the full interview here.

How early on in the planning of Series 4 did you know you’d have Matt Smith as a guest star? Following David Tennant’s story in Series 3, would you like to see an appearance by The Doctor become a regular event each series?

“We pretty much always knew we were going to bring Matt into the series. And it was wonderful to have Russell [T Davies] come back and write that story. But I’m not sure about bringing the Doctor into every series. We have to remember that this is The Sarah Jane Adventures, and Doctor Who is another show. Crossing the boundary is fun every now and again, but I’m not sure we should do it all the time.”

“This was a great opportunity for Sarah Jane to meet the new Doctor - and to meet Jo Grant - so there was a good reason for this story. But I’d be wary of him coming back too much; it just starts to look like a stunt. Schedule-wise for the two shows it can be a logistical nightmare, too. Having said that, I’m sure he’ll be back again some time. I hope we see Jo again, too.”

And how about appearances by previous Doctors? It’d be amazing to see Tom Baker with Elisabeth Sladen on Bannerman Road!

“I think there’s a part of all of us that remember Lis and Tom together that would love to see the Fourth Doctor turn up one day. And who knows?!”

Now that Doctor Who and The Sarah Jane Adventures no longer have the same show-runner, do you still see the two shows existing in the same fictional universe? (For instance, did Luke, Clyde and Rani also forget about the Daleks due to the crack, etc.) Or do you try not to worry about these things too much!

“The wonderful thing about this universe is: it can be any universe! Make your choice. Which universe do you want it to be? Is it a universe that looks just like the one with the crack, but isn’t? How would we ever know? I think I’m skating the issue here!”

Without giving too much away about the Series 4 finale - intriguingly titled ‘Goodbye, Sarah Jane Smith’ - hypothetically can you imagine the show continuing if Elisabeth Sladen ever wanted to leave?

“Hypothetically, yes, we could continue to do the show without Lis. Whether we would want to is a completely different matter.”

How far underway is Series 5 of The Sarah Jane Adventures?
“We have three episodes in the can. And they are corkers! Series Four has been great, but wait til you get a load of Series Five. Oh, boy! Next time round we really go for it!”