So, what's it all about?

'Porridge' starring Ronnie Barker and Richard Beckinsale is a Situation Comedy following the lives of Prisoners who are serving time in 'Slade Prison'.

Ronnie Barker is the main protagonist in this brilliantly funny programme and his character Norman Stanley Fletcher, 'Fletch' to his closest friends (and enemies!) drives the episodes with wit and superb comic timing.
Fletcher is serving a 5 year stretch for his crimes and during his time, he encounters a variety of in-mates, ranging from a young, scared first-time prisoner in the shape of Lennie Godber (Richard Beckinsale) to an experienced, bitter Prison Officer named Mackay, who is portrayed by Fulton MacKay.
Fletcher's journey includes many scrapes and adventures, and along side the hilarious comedy this all makes for great family television!

Here is a comprehensive summary of the programme, including a cast list, from the bbc website: http://www.bbc.co.uk/comedy/porridge/