The Sarah Jane Adventures: The Man Who Never Was, Part One - Next Time Trailer

Joseph Serf has launched his new SerfBoard, the must-have computer that no one can resist owning. Intrigued, Sarah Jane takes Luke and Sky to investigate what's so compelling about Serf and his business.

Clyde and Rani take a SerfBoard to pieces, suspecting alien technology may be the answer...

The first part of the last ever Sarah Jane Adventures story will be broadcast on CBBC on Monday at 5.15pm.