Ah yes, of course. Doctor Who always ends with the regeneration. The Christmas special picks it up immediately.I'd forgotten about Captain Jack. Are you aware of the excellent spin-off, called Torchwood? It is a slightly more adult take on the Doctor Who world. They don't really do crossovers (except Jack is a regular guest on Who and the whole team were involved against the Dalek's once), but their stories sometimes deal with the fall-out from the Doctor's escapades. There's another spin-off called The Sarah Jane Adventures, which is very much for younger kids, but does feature the wonderful K9. They were reintroduced via the proper stories and I think a scene with K9 and Mickey in a car is my favourite. I seem to remember Giles was the villain that week! Oh, and Spike popped up in Torchwood too.