Jon Hamm is ''very playful'' with his co-stars.

The 43-year-old actor - who has been in a relationship with actress Jennifer Westfeldt for 17 years - stars as unemotional Don Draper in drama series 'Mad Men', but Lake Bell, who appears alongside him in US biopic 'Million Dollar Arm', insists he is nothing like the character and is actually quite comical off-screen.

She said: ''He's actually very playful and funny, not like his characters, who are always stoic and brooding.

''I've known Jon for many years; I think we first met backstage on 'Saturday Night Live' but this was our first opportunity to really work together.

''He's great and it's always nice when you built-in rapport.''

Lake, 35, is also good friends with Cameron Diaz and Eva Longoria and she admits it was surprisingly easy to convince them to star in her 2013 indie movie 'In A World...', which she starred in, wrote and directed.

She added to Stylist magazine: ''Both are really good friends so I was like, 'Will you make a fool out of yourself for five minutes?'

''They're phenomenal, there's a reason they're both working all of the time. They're just both so self-deprecating.''