Two and a Half Men was one of the most successful tv shows of its time, while also battling a constant deluge of criticism from critics for its crass humor, objectification of women, the glorification of lead character Charlie Harper's decadent lifestyle, and leading man Charlie's Sheen's notoriously explosive private life.

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Despite the controversies, the show kept chugging along until its twelfth season. In all that time, the only constant was Charlie's sibling Alan, who went from playing second fiddle to his brother to essentially becoming the show's lead. Here are 10 questions that are finally answered about the longest recurring character on the show.

Is He Really A Doctor?

Not really, no. Although Alan would vigorously try to convince you otherwise. He is a chiropractor, with a degree in the field from a foreign school of extremely dubious reputation. Alan likes to think he is just as good of a doctor as anyone else and rues the fact that society and his brother, in particular, are always making fun of his profession while accusing him of practicing quack medicine on gullible patients.

Despite the insults, Alan has been shown to be quite competent in his field, helping fix a few spinal problems of his near and dear ones, and running a somewhat-successful chiropractic practice in LA.

How Did He End Up Living With Charlie?

Two and a Half Men Alan Harper and Judith

After his marriage with Judith failed, Alan got divorced and found himself paying huge alimony, severely limiting his resources. As a result, he was forced to move in with his brother Charlie at his Los Angeles beach house, along with his son Jake.

This was supposed to be a temporary arrangement, but one thing led to another, and Charlie got so comfortable living rent-free in a beach house that he started actively resisting Charlie's increasingly blunt attempts to get him out of the house. Even when Charlie passed away and the house was handed over to new owner Walden Schmidt, Alan managed to stay on as Walden's roommate, bestie, and temporary husband.

Wait, What? Alan Was Married To A Dude?

Two and a Half Men Alan Harper and Walden marriage

Yeah, but not in a gay way. In a strictly bro-help-me-get-a-kid way. Walden, played by new series lead Ashton Kutcher, had been having bad luck with relationships for quite some time. He finally decided to give up on finding a soulmate all together and adopt a child instead, hoping to fill the hole in his life left after his failed marriage and later engagement.

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Since adoption agencies don't like handing kids over to bachelors, Walden hit upon the idea of marrying Alan, reasoning that since they lived together, they were practically married already. Even though Alan is straight, he couldn't say no to his best friend and billionaire, so the two tied the knot.

Did Alan Get Along With His Brother?

Alan's feelings towards his brother are complicated, to say the least. Having spent his life being the traditionally 'good' brother, he often felt angry at seeing his best efforts end in abject failure; meanwhile, Charlie's drinking, gambling, and womanizing ways were bolstered by good looks, excellent health, and a lucrative, easy job as a Hollywood jingle writer.

Alan has also revealed a desire to be more carefree like his brother, like the time he pretended to be Charlie and adopted all his irresponsible ways. Charlie, in turn, views many of his brother's actions as weak and pathetic, but recognizes the good in him, enough to allow him to live rent-free in his house for a decade, albeit often begrudgingly. In fact, Charlie once gave up on the chance to be with the love of his life because it would have meant throwing Alan and Jake out of his house.

Does Alan's Son Worship & Adore Him?

Two and a Half Men Alan, Charlie, and Jake

Alan would sure like to think so, but both Jake and Charlie would probably laugh for five minutes straight at the question. After seeing his father fail at marriage, live on his brother's goodwill, be subjected to a constant stream of taunting and criticism from Charlie, his mother Judith, his grandmother Evelyn, housekeeper Berta, and all of Alan's girlfriends, whatever respect Jake had for his father has diminished practically to non-existence.

Despite this, Jake feels genuine affection for his father, recognizing him as someone who tries to do good and the right thing, most of the time. It's safe to say Jake looks up to his uncle as a man more than his father, even while being fully aware of Charlie's many flaws.

What's The Worst Thing Alan's Ever Done?

It's a pretty long list, and Alan can generally find some way to explain away his most scummy behavior. How about the fact that he lived rent-free with Charlie for years, yet constantly criticized him for his lifestyle choices? Or how Alan grew more dismissive of his own son as the show went on? There was also mention of an incident which was never fully revealed involving Alan, a dog, and peanut butter.

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Alan has cheated on many of his girlfriends, once with the girl's own mother. He has assumed his brother's identity, and on more than one occasion considered killing Charlie, and himself. But perhaps worst of all, Alan is most probably the secret father of Judith's daughter while she was married to another man.

Who's Alan's Special Someone?

Alan and Lyndsey talk while sitting on a couch

Alan has dated a number of girls, most of them being way out of his league. He was married to brainless bimbo Kandi briefly before getting divorced again. Alan also dated his receptionist before screwing things over by sleeping with her mother.

By far Alan's most serious relationship was with Lyndsey, a single mother who seemed fine on paper, but was often shown to be almost just as screwed up as Charlie on the inside. Even that relationship did not ultimately last, and it was hinted in the series finale that Alan was doomed to stay single and live at the beach house for the rest of his life.

What Childhood Tragedy Made Alan Turn Out This Way?

Alan did not have a happy childhood. A running theme of the show is how terrible a mother Evelyn was to both Charlie and Alan, being too caught up in remarrying and enjoying her life to focus on her sons. Evelyn would constantly belittle and dismiss Alan's accomplishments, a habit that continued in his adult years with Alan never really getting any kind of closure over his mommy issues.

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Charlie was also not a very supportive older brother, stealing Alan's dates and playing practical jokes on his younger sibling. Basically, Alan spent his formative years being beaten down by the people closest to him, a trend that continued into adulthood through his emasculating relationship with Judith.

Does Alan Ever Find Happiness?

Despite being perennially down on his luck and in need of help from those around him, Alan manages to put a positive spin on most things in his life. His optimism ran out once and he tried to take his own life, but that attempt was unsuccessful.

It is hinted that while Alan will never find happiness in a relationship, he will still spend the rest of his life in luxury, living in the beach house with his billionaire buddy Walden.

Is That Really Alan Singing In The Theme Song?

Chuck Lorre has confirmed that the opening theme song of the show, which is accompanied by a clip of the three leads singing along to the tune, is a lip-synced performance. The actual tune is sung by studio artists.

Alan might be a lot of things but a singer is definitely not one of them. To be fair, this is something he shares with Charlie, Jake, and Walden.

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