Robson took a deep breath before plunging into his latest role in the new six part drama series Close and True. The setting was the crystal clear waters off the Maltese island of Gozo, and Robson was playing a lawyer on holiday, learning to scuba dive. It was a daunting moment as he donned wet suit and breathing apparatus, and prepared for his first dive. "I have no fear of water, and I was happy to go down to ten metres. But I am afraid of big fish. If you are going to go, you don't want to be eaten by a fish. So it was a bit scary," confesses Robson.

Robson trained with a scuba diving expert in a swimming pool before travelling to Gozo, which is a mecca for diving enthusiasts. On each deep-sea dive he was surrounded by a team of experts to ensure his safety. "It was an exhilarating experience, but I didn't think I'll take up scuba diving as a hobby," he says.

In Close and True Robson plays John Close, a shy and polite man who has been working - not very successfully - as a commercial lawyer in London. He decides to change his life and take over a virtually bankrupt legal practice situated on the banks of the Tyne.

But his idealistic crusade to give a voice to people who can't afford legal representation is not quite what he imagined: "The practice has run down to the point of collapse and is staffed by people who have accepted its inevitable failure. John sees he has been wasting his life, and that this practice actually can change other people's lives for the better. John suddenly realises that with a massive effort on his part, he might be able to turn its fortunes around" explains Robson. "But John is a commercial lawyer with experience in balance sheets and business plans. In terms of criminal law he is totally out of his depth."

John ploughs all his money into the practice, and also secures a loan from his ex-girlfriend Jessica in an attempt to salvage the business. "The senior partner Mr. True is living out his life in a mental home. But he has an incredible mind. When John is unsure of things he goes to Graham True to ask what to do and he realises what a genius Graham True is. Graham True was like John once - full of ideals, fighting on behalf of the underdog, and warns John not to continue his pursuit or he will end up on a psychiatric ward too."

The two men strike up an odd friendship, and agree to become partners in a new practice - Close and True. Robson was highly daunted when he prepared to play his first scenes with the actor playing oddball Graham True - his childhood hero, James Bolam. "I was very nervous before James arrived on set. I had never met him, but I had always been a huge fan because of When the Boat Comes In, The Likely Lads, Beiderbecke, and End of the Affair. He is such a fine actor. Here was someone I had always held in high esteem, and I was going to work with him for the next four months- it was nerve wracking. But he's an absolute gentleman and told me what a pleasure it was to work with ME!"

"We just hit it off. He has beautiful timing, and he can speak without talking. He has got IT. Sometimes when the camera wasn't on me, I would watch James working and his CV would be going through my head, and I would forget my lines. When we finished working together he gave me a hug and said it had been fun. And it was fun. He has great anecdotes to tell. When that was happening off camera, it just got better in front of camera."

Robson knew James Bolam would be perfect for the role: "When I first heard James had agreed to take the part I felt the same euphoria as when I got my first job. When you have James Bolam you know he will bring warmth to the show."

The character of John Close is quite different to some of the romantic leading roles he has become best known for recently. John is a more vulnerable character and is very shy with women. Very old fashioned, he feels uncomfortable in casual clothes and prefers traditional suits, and has bookish spectacles perched over the trademark blue eyes. "John Close is an honest and true man. But he's no good with women because he can't articulate his feelings, and he's spent his life so far following a fairly meaningless career to please his dad. Now he has the chance to do something with his life. What makes this series different is that it isn't just courtroom drama. It's a show about human beings and their strengths and failings, with a great mixture of pathos and humour. I think the warmth of the show will come from that. The legal pursuits in each episode are just a backdrop."