Welcome to Walt Willey's Flashback Friday Fun Foto Facts

Here's the FFFFF:

Okay, so the last few Flashback Friday Fun Foto Facts questions have been really easy.  I admit it.  So let's crank it up a bit this week.  Again, to celebrate the the Wild Bill! An Evening with James Butler Hickok Fall Tour, here's the question:

There were many famous scouts, but few more famous than "Wild Bill" Hickok and "Buffalo Bill" Cody.  Here's a picture of Hickok (l) and Cody (r) and standing behind him is their co-star in the show Scouts of the Plains.

Who is this plainsman?  Post your answer below.