The Doc Martin star is keen to do a documentary movie about Tony, who was awarded an OBE in 2006 for his conservation work with wildlife in Africa.
"We're hoping to make a film about a friend of mine in Africa - Tony Fitzjohn - who lived and worked with George Adamson setting lions free in Kenya," he said.
Animal lover Martin, who has made programmes about dogs and horses, hopes to meet some lion cubs.
He added: "Tony is a great mate of mine and a good story, and we wanted to make a film because he's going back to Kora, where George was murdered, and he's going to start releasing lions again, I think. He's got the permission to do that so hopefully, I'll get to be up close and personal with some baby lions."
:: The fourth series of Doc Martin is available now on DVD.