Lily Tomlin stays silent on her chat with Obama, Chris Hemsworth says Thor changed his life, Ron Howard says he is surprised by his success and Kevin Bridges confuses Lily with his accent, while Shirley Bassey and Blake perform live in the studio.

Lily Tomlin, talking about receiving a Kennedy Center Honour from President Obama, and the moment she got up in the middle of his speech to whisper something in his ear, she says, "I felt the urgency to get up and speak to him." Asked what she said, she jokes, "I can't divulge it. Only the President and I know what I said - and of course, Edward Snowden!"

Talking about her new movie, Grandma, which she describes as, "Funny, interesting and kind of important," and the Oscar nomination speculation that is circulating about her performance, she says, "I have been exposed to the buzz but I don't have any expectations."

Jokingly adding, "If I win I will be very humble of course but I'd like to wheel on a box that has a niche prepared for the Oscar next to the Emmys, Tonys and Grammys! But I don't think it will happen."

Asked about performing in prisons in the US some years ago, she says, "I was horrified but willing to learn and reach out. It was a miserable experience. I was escorted for three days by a young girl, who said at the end of my visit that she would write a kind review for the prison magazine. It turned out she was one of the Manson women!" Asked if the review was good, she says, "I still have it - it wasn't kind enough, at least not in my book."

Ron Howard, talking about his amazing track record of picking box office hits, says, "Many of the movies that made the top ten box office hits surprised me. I've never had any expectation about the films I make. I had no idea Cocoon would be such a success I just loved the story, or that Apollo 13 would necessarily be a big hit, but it was a great story. I really just chose from the heart and I have been very lucky."

Asked about casting his family in his films, he says, "I do it whenever I can. I love working with my family and my wife has been in everything I have ever directed since high school. I was directing a short aged 16 and needed a saloon girl and she was it. She's the good luck charm and you can spot her in every movie if you know what you are looking for."

Revealing he is careful to only cast his family in ways that he knows they can succeed, he says, "I got a call from my dad suggesting my mom would be great as Jim Lovell's mother in Apollo 13. I told him it was a tricky role and that I would have to audition her." Asked how that went down, he says, "I worked through the scene with her and she was great. I've never been prouder." Adding, "What was really bad was making a call to my dad - he is a great actor and he did great but the scene was a bit long and he got cut. When he asked if he was in it at all, I said, 'Maybe in the extended DVD cut...' That was a tough call."

And on tackling his new epic movie In The Heart of The Sea, which stars Chris Hemsworth and is based on the true story that inspired Moby Dick, he says, "Directorially, it was the biggest of challenges but I have an ambitious streak that I just have to follow. It's a life experience making this type of movie - I'm not naturally adventurous as a person and these movies take me to places and experiences that I wouldn't otherwise have."

Talking about winning the Oscar for A Beautiful Mind and being presented with it by Mel Gibson, he says, "I saw Mel at a party before the ceremony and he said, 'I'm giving out the director award and I am going to give you an award' and he is just outrageous enough to do whatever he wants to do. So when he announced I had won I demanded to see the card. It did have my name on. I was greatly relieved!"

Chris, talking about his In The Heart of the Sea role, says, "It was the most physically challenging thing to do." And on the dramatic weight loss he went through for the role, he says, "It was a crazy diet and sometimes when 'cut' was called you would literally pass out from exhaustion."

Asked about Thor, he says, "It changed my life - it got me a job and I was able to pay the rent, which was nice and it opened up every opportunity in my career." Asked if it was awkward after his brother Liam was rejected as Thor before Chris was cast in the role, he says, "It was fine. He actually helped me go back in (for the audition). It was a team effort."

Talking about his acting family, and asked if he, Liam and his other brother Luke, might act together in a film, he says, "I think if the right thing came up we would but you could only do it once otherwise it becomes very Brady Bunch!"

Asked about moving back to Australia with his family, he says, "It just got too insane with all the paparazzi and living in LA with three kids wasn't conducive to the life we wanted to live." Talking about the selfies he has posted online with giant spiders and snakes in his Australian home, he jokes, "It's like Jurassic Park. I am surprised and relieved when I go in to see the kids that they are still in the cot!"

Kevin Bridges, talking about his success and the fame that has come with it, says, "I have had lots of reaction from people and have even been asked to sign 25 pirate copies of my own DVD - that took some balls!"

Talking about his Glaswegian accent, which Lily struggles to understand, Kevin says, "I did a gig in the States and a guy approached me after the set and complimented me. He then said, 'Are you actually Scottish?' when I said yes, he said, 'Man, your English is pretty good.'"

Chris adds, "When I did The Huntsman it was meant to be a Scottish accent but I just gave it a Celtic vibe. I had one reviewer that said it was worst Glaswegian accent since Fat Bastard! In my defence it wasn't a Glaswegian accent it was a Celtic, fantasy, Snow White, Scottish influence world, which gives you a broad range to do whatever the hell you want!"

Asked about performing from a young age, Kevin says, "My dad would drive me to gigs - as I was 17 I could only perform in a pub if I brought along a parent - it was so uncool. It was even more tragic when my mum would start showing up! At some gigs I would double the audience with my family." Adding, "My material was just teenage stuff including a routine about waking up with an erection. I committed to telling the story and looked up to see my aunty Maureen, my mum and dad and my uncle George in the audience. My mum looked at me as if to say, 'What have we raised?'"

On his own weight loss, he says, "I took a year-long sabbatical from booze and when you're not hung over at the weekend you take up exercise. It was a wee personal challenge." Adding, jokingly, "I'll be back - I'm only one inclusive holiday away from melt down!"

Talking about when he performed in a prison, he says, "One guy stood up about 10 minutes in and went back to his cell... it was the worst sort of heckle - he must have thought, "This guy is rubbish, I'm away to finish my life sentence!'"

Shirley Bassey and Blake perform The Christmas Song live in the studio before joining Graham for 'Dame Shirley Bassey' cocktails and a chat.

Talking about the potential of the song getting to number one in the charts, Shirley says, "I have never done a Christmas song before. It's my very first. Every time I asked the record company if I could do one they said no. I think they were afraid because of my voice. No one could imagine me belting out Silent Night!"