Per page 730 of the book, A Million and One Nights: A History of The Motion Picture Through 1925, by Terry Ramsaye:

In 1919 a quartet of brave conspirators met to form the Supreme Pictures Corporation to rehabilitate the status of the serial with a master effort in mystery and detective story thrills. It was to be a million dollar corporation, etc. In electing officers they decided to leave the presidency to the toss of a coin.

Louis Grossman, the business man of the party, flipped a quarter in the air. It struck the desk and rolled off on the floor.

Then the august directors of that million dollar corporation spent a half hour on hands and knees searching for the missing twenty-five cents.

The baffled searching party included John W. Grey, mystery scenario writer, Arthur B. Reeve, author of complex detective tales, and–Harry Houdini.

The corporation has faded and the quarter is still missing.

Per a side-note at the end of the June 11, 2014 Classicfilmaficionados post (titled Terror Island! A Cliffhanger, but not a Serial, starring Houdini) by C S Williams:

In autumn of 1919, John Grey, Arthur Reeve, Harry Houdini, H. Sumnich and Louis Grossman decided to form a new motion picture production company with Grey installed as president and Reeve as vice-president;[111] the company’s purpose was to rehab the serial genre.[112] The studios were located at Flushing, Long Island, New York.[113] The young company had a contract with Goldwyn, indeed, it is stated that the purpose of forming Supreme Pictures was to produce four Craig Kennedy pictures a year, over an undetermined number of years; what happened to stall that deal?[114] And what happened to the purpose? It is most likely not one impetus, but many that drove the group to establish Supreme Pictures.

Yet, the genesis may be found (at least Reeve’s reason) in Arthur Reeve’s attack on Democratic Senator Thomas Gore (grandfather of Gore Vidal, and a distant relative of Al Gore) of Oklahoma and his bill; Gore had introduced legislation to prohibit Interstate transportation of “blood and thunder” films or still pictures. Reeve was impassioned regarding the subject, and he deftly argued his points, simultaneously defending thrills in general, making mention that if Gore’s bill succeeded it would create a “namby pamby world.”[115]

But the Supreme Pictures Corporation lasted but one project and was done by the following year. The Mystery Mind, released in November of 1920, was the sole serial and only title for the company. Grey and Reeve collaborated on the writing (not uncommon for this pair), as well as acting as the producers of the fifteen-chapter photo-play[116]. Houdini was not involved in the making of the picture, and of course Grossman being the financial expert, took care of the business end.

[111] Exhibitors Herald, January 24, 1920; Wid’s Daily, May 24, 1920

[112] Motion Picture Daily, July 2, 1953

[113] Exhibitors Herald December 6, 1919

[114] Wid’s Daily, May 24, 1920

[115] Exhibitors Herald, January 24, 1920

[116] Exhibitors Herald, January 24, 1920

Per Motion Pictures News December 27, 1919:

Reeves of Supreme Pictures Promises Something New in “The Master Mind”

“The secret of serial success nowadays is to put over a new idea in every serial,” said Mr. Reeve, who is vice president of Supreme Pictures. “My ‘Exploits of Elaine’ made science famous in the movies with Peral White and Arnold Daly who played Kennedy, scientific detective. ‘The House of Hate’ had a central theme, the crushing blight of war and making millions out of the blood of our fellow men. Houdini and his marvelous escapes and feats were the new feature of ‘The Master Mystery’ and our ‘Grim Game’.”

Per The Moving Picture World January 3, 1920:

New “Master Mind” Serial Has Unique Mystic Villain:

“A serial is known by its villains, in fact a serial is made by its villains”, said Arthur B. Reeve, author of the Craig Kennedy stories and vice-president of Supreme Pictures, who is directing the Robert Pauline serial, The Master Mind.

“I may say in connection with the eight successful serials I have written, that in the The Master Mind Mr. Grey and I have the most unique mystical villain we have yet conceived. For example, the first serial I wrote, The Exploits of Elaine, had the famous Clutching Hand. In the House of Hate there was the Hooded Terror. One of the weirdest conceptions, I think was our Automat in the Houdini serial. Here in the Master Mind the great serial dealing with Hypnotism and the science of mind, we have two villains.”

Per The Moving Picture World January 31, 1920:

Supreme Pictures Officials Noted for Their Past Serial Successes

John W Grey became head of the scenario department for Pathe, supervising productions, among them many serials. Connection with Pathe brought Reeve and Grey together. Together they wrote “The Master Mystery” and “The Grim Game” for Houdini.

Note: In honor of Houdini and The Master Mystery serial, it is fitting that  “The Master Mind” serial became “The Mystery MInd” serial.