How many muscles do our fingers have?

Contrary to popular belief, your fingers contain absolutely no muscles. Instead, your digits function like a sophisticated puppet system, operated by extrinsic muscles located in your forearm and intrinsic muscles within your palm.

https://www.scienceabc.com/humans/hand-fingers-no-muscles-phalanges-bones-tendons

Here's an interesting experiment that demonstrates that there are no muscles in our fingers:

https://www.youtube.com/watch?v=p6_khJUIvmE

However, Stephen Fry is wrong to say that the middle and ring fingers have a shared tendon. In fact, their individual extensor tendons are physically tied together by an anatomical bridge. This connection is why you cannot lift your ring finger if your middle finger is bent flat on the table, as shown in the video.