Based on the book King of Heists: The Sensational Bank Robbery of 1878 That Shocked America, written by J. North Conway. An unassuming man in the elite New York society assembles a crew that pulls off the largest bank heist in American history in 1878.

Based on a true story, an unassuming member of elite New York society pulls off the largest bank heist in American history in 1878.

Why mention the book source or author at this point? It only gives a director or producer a reason not to read the script or to approach it with a negative frame of mind for the reason Wilsondowndunder cited.

The purpose of a logline is not to give a producer or director a reason to reject the script. but to give them reasons to read it. So get them interested in the concept, make them fall in love with the script.

[That it’s an adaptation is a separate issue. One a screenwriter would do well to obviate by obtaining adaptation rights beforehand, if possible The cue for the supporting cast of lawyers and literary agents to enter stage right…]