Charlie Sheen does not play the piano on the show. He is dubbed by composer Grant Geissman, who plays offstage while Sheen fakes it on a dead keyboard. With composer Dennis C. Brown, Geissman also writes the music for the jingles Sheen's character creates.
Jon Cryer won two Primetime Emmy Awards for playing the role of Alan Harper. His first Emmy win was for Outstanding Supporting Actor in a Comedy Series (when Charlie Sheen had the leading role of Charlie Harper). After Sheen left (and Ashton Kutcher came on-board as the character of Walden Schmidt), Cryer won his second Emmy as Alan Harper, this time in the Outstanding Lead Actor in a Comedy Series category.
It is revealed that Charlie was a planned child whilst Alan was only conceived because Evelyn "didn't want to smear her lipstick." Evelyn also told Alan he was the product of "a pitcher of Margaritas and a gas-station condom".
Rose was originally written off near the end of season four by having her move to London, because Melanie Lynskey had landed a part on the FOX pilot, Drive (2007) When that show was canceled, she was allowed to return to Two and a Half Men.
Filming had to be interrupted during season 7, when Charlie Sheen checked himself into rehab in February 2010. Sheen's time in rehab was related to a domestic violence incident with his wife Brooke Mueller on Christmas Day 2009 after which he was charged with felony menacing, third degree assault, and criminal mischief.
Production was halted during the eighth season due to Charlie Sheen publicly making disparaging remarks about CBS and creator Chuck Lorre. Only 16 episodes were produced that season instead of the usual 22 to 24. CBS and Warner Bros. terminated Sheen's contract. He was replaced with Ashton Kutcher in the ninth season.
At a convention of television critics during the summer of 2005, executive producer Chuck Lorre confirmed that the show's opening tune is performed by studio musicians and not by actors Charlie Sheen, Jon Cryer and Angus T. Jones (who merely lip-sync the lyrics). One of the actual crooners is singer and voice-over artist Elizabeth Daily.
In Two and a Half Men: Twanging Your Magic Clanger (2010), the pornographic website Charlie gives Alan when he walks in on him doing his (business) is malibupuddinggirls.com, if you search this on your browser it will lead you to the official two and a half men Facebook page.
In 2012, Angus T. Jones (who plays Jake) appeared in a video for the Forerunner Seventh Day Adventist Church in which he talked about his religious beliefs and observances. He also criticized his TV show on religious grounds, saying, "Jake from 'Two and a Half Men means nothing. He is a non-existent character. If you watch 'Two and a Half Men,' please stop watching 'Two and a Half Men.' I'm on 'Two and a Half Men,' and I don't want to be on it. Please stop watching it; please stop filling your head with filth. Please. You know, people say it's just entertainment. The fact that it's entertainment...do some research on the effects of television and your brain, and I promise you you'll have a decision to make when it comes to television, and especially with what you watch on television. It's bad news....I don't know if it means any more coming from me, but you might not have heard it otherwise. Just watch out. Watch out. A lot of people don't like to think about how deceptive the enemy is. He's [the devil has] been doing this for a lot longer than any of us have been around. So we can't play around. There's no playing around when it comes to eternity." Jones subsequently apologized to the cast and crew for any "indifference and disrespect" he showed to them, while not disavowing his views on the show itself. As a result, Jones was removed from the regular cast after the 10th season. (Jake stated that he was transferring to Japan.) While he was announced as a "recurring character" for Season 11, he no longer appeared on the show. In 2014, Jones officially announced his departure from the show stating that he had been "a paid hypocrite". Nonetheless, Jones returned for the series finale, with Jake explaining that a cash bequest from Charlie led to his winning "two and a half-million!" during a Las Vegas honeymoon, which he and his new bride invested.
Alan's cell phone's ringtone in the beginning of the series is Ludwig van Beethoven's "Für Elise". In later seasons, his ringtone is a possibly covered version of Fifth Dimension's "Up, Up, and Away." One of the show's running gags is Alan's cell phone ringing at unexpected times and places.
Hugh Grant was originally signed to replace Charlie Sheen. His character was to be smooth-talking con man who tricks Alan into letting him move in without paying rent. But Grant decided that he did not want to commit to multi-year contract for a television series and backed out of the role.
Charlie Sheen was fired from the show in March 2011. The show went initially on hiatus during filming season 8 due to Sheen undergoing a substance rehabilitation program. However, following what was only supposed to be a short hiatus, Sheen had a highly publicized meltdown. Besides making anti-semitic remarks towards series creator Chuck Lorre, he made bizarre statements in television interviews, suggesting that he was a "warlock" with "tiger blood" and "Adonis DNA", and that he was "winning". He also posted videos to YouTube showing himself smoking cigarettes through his nose, and cursing out his former employers. The dismissal of Sheen caused the show to cease production for the rest of its eighth season. The ninth season started with Ashton Kutcher, who was announced as Sheen's replacement in May 2011, as co-lead with original cast-member Jon Cryer.
In the opening credits, where the theme song of the show is played Jake (Angus T. Jones) is usually seen growing from a young child to what he currently looks like according to the episodes. However in the later episodes of season 9, Walden's hair becomes shorter and his beard disappears at the end of the theme song indicating his recent new look in the show.
For a short period of time, Walden used the false name of Sam Wilson. Samuel Wilson (September 13, 1766- July 31, 1854) was a meat-packer from Troy, New York whose name is purportedly the source of the personification of the United States known as "Uncle Sam".
Watch the opening theme song during the later seasons. During the song, Angus T. Jones appears as young as he was during the First Season, but at the end of the song in later season, he "morphs" into the age he is for that particular season.
Product placement (seeing a clearly-identifiable product label on a shelf or in a person's hand) is a study in contrasts in this show. In almost every instance where hard liquor is seen, the front label of the container is facing away from the camera. Other products often are disguised or hidden. In Season 5, however, the presence of a can of Cafe Bustelo coffee in the kitchen almost steals the scene away from the actors. (Maybe it's the bright yellow and red label?) In every episode from Two and a Half Men: Media Room Slash Dungeon (2007) (Season 5, Episode 2) to Two and a Half Men: Shoes, Hats, Pickle Jar Lids (2007) (Season 5 Episode 9) a bright, clearly-readable Cafe Bustelo can is on the Harpers' kitchen counter. In Two and a Half Men: City of Great Racks (2007) (Season 5 Episode 4), a large, lighted advertising sign for the product also is seen on the counter of the local coffee shop. (In subsequent episodes after No.9, Cafe Bustelo is not seen again, replaced, it seems, by the more subdued but still recognizable packaging of Don Francisco brand coffee.)
From time to time, and usually during the Charlie Sheen days, members of the old "brat pack" would make guest appearances on the show; for example, Judd Nelson appeared as the ex-husband of Alan's girlfriend, also Emilio Estevez and Martin Sheen (Charlie's brother and father, respectively) have made appearances on different episodes, as well as Ally Sheedy.
Error: In S10E08 ("Two and a Half Men: Something My Gynecologist Said (2012)") Alan meets his older Alter Ego, Sid Olsen, in a bar. Before Sid leaves he gives Alan his business card with the back side visible before the cut. After the cut the card shows the front side with letters "CPA" in an oval.