The image is an engraving after a painting in oils by August Schoefft titled The Thugs. It was sold in auction in 2009. See the link for more about this remarkable work of art: http://www.christies.com/lotfinder/paintings/august-theodor-schoefft-5234717-details.aspx

There existed in India a criminal tribe known as THUGS ,and it was British who eliminated the tribe and made a change over in their lives. The thugs were cruel and masquerading as members of yathris used to loot and kill without leaving a single member alive Most often THE victims were pilgrimages or some rich traders.

With the brahmana and his student on the left and the musicians on the right, I wonder if this really a party of thugs, or a compilation of personalities and groups whom the artist saw.

A party of thugs....and he gets to sketch them..!!