Having flown back from New Zealand, where he spent the best part of 2011 filming The Hobbit, James Nesbitt returned to the set of St Matthew's hospital dressed as the charismatic neurosurgeon, Monroe.
Although there was little preparation time before filming began, Nesbitt felt at ease with the direction writer and series creator, Peter Bowker, has given the second series.
"I think Pete is incredibly intelligent and his work is amazingly engaging to an audience. He really understands how people talk and think and he creates real characters that people find believable," he says.
Nesbitt was in New Zealand when he got the call letting him know that a second series of Monroe was going to happen.
"Being away I didn't really have an opportunity before filming started to sit and chat with Pete about what was going to happen to Monroe in the new series which hasn't really happened before, but I trust Pete so much that I was very happy for him to just get on with it."
So thorough with his own research for the first series, portraying a neurosurgeon now comes naturally to Nesbitt.
"The cases are always very different but I am so familiar with theatre now and I understand the shorthand - how to read scans, how to understand what they are telling me in a short space of time and I know what to do to make it look authentic so I feel comfortable with all that now. The more authentic I feel, the more authentic I will be."
To make the show as realistic as possible, Nesbitt is getting advise from real life surgeons and nurses.
"They're on set all day with us when we're filming the operation scenes. They'll come in and show me what to do and how to position myself," he says.
The surgeons and nurses on set will watch the whole time and say if something's not quite right.
For me as an actor it's an exciting challenge to get it absolutely right."
Monroe is screened on Prime, Sundays at 9.45pm.