Movie star Armie Hammer has teamed up with artist pal Tyler Ramsey to shoot a new video project featuring people cutting themselves.

The two friends hope to release the finished piece to raise awareness of atrocities occurring in Africa.

Hammer tells Nylon magazine, "The idea was there are all these massacres happening and we can't do anything about them, so we'll spill blood for their blood.

"We filmed people cutting themselves. It's an interesting process to watch everyone's self-preservation instinct kick in... It's really difficult to cut yourself to draw blood."

But one of The Social Network star's famous friends went too far and left the actor squirming when he sliced into his breast just above his nipple.

Hammer recalls, "It really changed the tone of the whole thing."

The actor and the artist have no firm plans to release the footage they have so far, with Hammer explaining, "It's a long-term project."