Sherlock Jr. is a 1924 American silent comedy film starring and directed by Buster Keaton and written by Clyde Bruckman, Jean Havez, and Joseph A. Mitchell.

In 1991, Sherlock Jr. was selected for preservation in the United States National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant".

Projectionist buys a $1 box of chocolates, all he can afford, and changes the price to $4 before giving it to the woman he loves at her house.

When the Father notices that his watch is missing, the Sheik slips the pawn ticket into the Projectionist's pocket unnoticed.

Fearing that they will be caught, the Villain and the Butler attempt to kill Sherlock Jr. through several traps, poison, and an elaborate pool game with an exploding 13 ball.

It is believed that the idea for the film was a tribute to Oscar Heinrich, the forensic scientist involved in the rape trial against Arbuckle.

[3] Arbuckle became angry and abusive on set, yelling at actors and according to Keaton becoming "flushed and mad ... [the scandal] just changed his disposition.

Keaton later said that it was an old vaudeville trick that his father had invented, and he later performed it on the Ed Sullivan Show in 1957, but never publicly revealed how he did it.

[8] Keaton later told film historian Kevin Brownlow "every cameraman in the business went to see that picture more than once trying to figure out how the hell we did some of that.

Keaton later explained that this stunt was achieved through the use of lighting: "We built a stage with a big black cut-out screen.

[10][12] In 2014, the Dallas Chamber Symphony commissioned Craig Marks to write an original musical score for Sherlock Jr.[13] It premiered during a concert screening at Moody Performance Hall on February 25, 2014 with Richard McKay conducting.

Although audience members gasped at some of the special effects, there were very few laughs, and Keaton began re-editing the film to make it funnier.

Keaton considered the film "alright [but] not one of the big ones", possibly due to the fact that it was his first real failure after a 25-year career on stage and screen.

Edmund Wilson of The New Republic criticized Keaton's performance for not having enough character development and the film for having too much "machinery and stunts".

[8] Dwight Macdonald, in his book On Movies, notes the sophistication of the premise: the second half of Sherlock Junior cuts free across magical territory.

His doppelganger extracts itself from his sleeping body ... and walks down the aisle of the darkened theatre to climb up on the stage and into the society-crook melodrama being projected on the screen ...

There's no explanation for this or any other lapsus naturalis in this 1924 film which makes later efforts by Dalí, Buñuel and Cocteau look pedestrian and a bit timid.

It is more significantly, a great example of American minimalism—simple objects and movement manipulated in casually complex ways to generate a steadily rising gale of laughter.

"[20] Dennis Schwartz wrote that Sherlock Jr. is "one of Buster's superior silent comedies that's noted for his usual deadpan humor, frolicsome slapstick, the number of very funny sight gags, the many innovative technical accomplishments and that he did his own stunts (including the dangerous one where he was hanging off a ladder connected to a huge water basin as the water poured out and washed him onto the railroad track, fracturing his neck nearly to the point of breaking it.

[23] Sherlock Jr. was a major influence on Woody Allen's The Purple Rose of Cairo (1985), in which a character walks out of a movie and into real life.

In 2012, it was ranked number 61 in a list of the best-edited films of all time as selected by the members of the Motion Picture Editors Guild.

[28][29] In 1991, Sherlock Jr. was selected for preservation in the United States National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant".

[30] On April 17, 1924, between the makings of Metro Pictures' Mademoiselle Midnight and Sherlock Jr., Marcus Loew announced that the three companies intended merging.