He is an OB/GYN at the obstetric practice of Freedom Tower Women's Health Center, which he owns and runs.
Danny Castellano was born in 1974 and raised in Staten Island, a borough of New York City. He comes from a working class family. His mother worked long hours as a maid cleaning motel rooms; his father's occupation is unknown, as he left the family when Danny was 13.
Danny graduated from Columbia University's College of Physicians and Surgeons, where he specialized in obstetrics and gynecology. He did his residency in New York City with both Dr. Mindy Lahiri and Dr. Jeremy Reed; he was considered the best resident by Dr. Shulman. After residency, he was hired by Dr. Marc Shulman as a partner at the practice of Shulman & Associates.
Danny went through a bitter divorce after finding his wife, Christina, in bed with another man. He has no children from this marriage. His thoughts on divorce are negative given the reason for his fallen marriage with Christina.
- „Daniel Castellano, I'm the man that's gonna take a person out of you. I don't take that responsibility lightly, OK?”
As a doctor, Danny is hard-working, disciplined, ambitious, and driven to the point where he may be considered a workaholic. He takes his work very seriously and approaches it with both passion and dedication. In addition to working the usual 5-day week, he works Saturdays in an effort to serve more patients and bring in more money. As a boss, he is fairly demanding: he expects the staff to work the same hours he does, although he chooses to leave his partners to their own devices.
Danny considers himself "the best doctor in the practice" and has a strong desire to play a leadership role. For a while, he wanted to be head doctor after Dr. Shulman's retirement. This was a desire that became reality for a short period of time when Dr. Shulman retired. The reality proved to be very different from his fantasies, however. After Dr. Shulman retired, his patients left the practice to join the midwives upstairs. In an effort to keep patients and lure their former patients back, Danny took on the position of head doctor (without Mindy's consent) and offered 20% discounts to all patients, in addition to authorizing ads featuring Jeremy's face (another decision backed by Jeremy and not consented to by Mindy). Unfortunately, these practical tactics failed, and the practice's patients flocked to the midwives upstairs in droves. It was only after Mindy stepped in and appealed to the women on a personal level that they returned. Since then, Danny has worked with Mindy and Jeremy as a team, and not one partner has more power or authority than the other.
Danny is blunt, honest, and forthright. He is also extremely arrogant to the point of cockiness and believes himself to be the smartest man in the room. He describes himself as a "wealthy, single, heterosexual male" and "the best doctor in this practice." Very disciplined, he likes having a regimented lifestyle and often believes that his way is the only way. He maintains that people's personal lives should be kept separately from their work lives. However, most of Danny's personal relationships are facilitated through the workplace, and he often participates in personal conversations, despite his stance.
He has a very strong, intense personality capable of running over less assertive personalities; it is best tempered by someone who has an equally strong, assertive character. He is very vocal in his opinions (especially when it comes to Mindy) and often comes across as a jerk. Despite this, he cares deeply for the people around him and is very loyal and dependable. His respect is hard-won, but once won, it is also hard to lose. He is also incredibly passionate and approaches everything he does with great energy. He considers himself handsome and works hard to maintain his physique, working out regularly and eating healthy foods.
He is a real "man's man"-- his style is rugged and a little rough-around-the-edges. He's also a hothead and is ready to "knock someone out" at the drop of a hat. He is not one for social niceties and is typically unconcerned with other people's opinions of him. He prefers to lounge about in jeans and a t-shirt -- a sharp contrast to Jeremy Reed, who is a very smooth, well-dressed cad. He firmly believes that it is the man's job to protect his woman and care for her.
- „Danny – Was this the kind of guy who, if he heard glass breaking in the middle of the night, is he gonna jump outta bed, say 'stay here' and look through the house naked with a baseball bat, or is he gonna hide under the covers with you? ... Is this the kinda guy who is gonna get grossed out when you give birth or is he gonna dry your forehead and tell you you look beautiful while all that disgusting stuff is coming outta you? ...Is this the kinda guy who's not afraid to get into a fistfight at a Springsteen show because someone really disrespects him? I mean, he'll just put it out and he'll take 'em down right there, right now?
Mindy – Okay, now you're just talking about yourself”
- —Danny & Mindy[src]
His divorce with his ex-wife is a particularly sore spot for Danny due to its brutal nature and its recentness. Although he hides it well, the divorce severely impacted him, making him somewhat insecure in his dealings with women. By nature, he is guarded and cautious when it comes to emotions, and struggles to express vulnerability towards any girlfriend of his. This was evidenced by his relationship with "Eyepatch" (Jillian)-- instead of asking her for another chance when she broke up with him, he simply left, assuming that this was what she wanted. It was only after discussing the relationship with Mindy and Morgan Tookers that he went to Jillian's place of work to ask for another chance. He is also not the most observant when it comes to the emotions of those around him; unless vocalized or made blatantly obvious, he is often unaware of more subtle emotional currents. He is also not the best listener when it comes to details, but he does try.
Although Danny is often a jerk, he is capable of tenderness and kindness towards those he cares deeply about. His actions do not always translate well, but they usually come from a place of genuine good-heartedness and caring. For instance, when Betsy Putch feels insecure about her attractiveness in comparison to Shauna, Danny attempts to reassure her with endearing, older-brother type fumblings. He tries to handle Shauna Dicanio's attraction to him in the club by dancing with her at arms' length, afraid of hurting her feelings. And while he often teases Mindy and occasionally says cutting things, he is usually there to provide comfort and support when she really needs it.
Danny is a devout Catholic who attends mass every week. Mindy has commented that "he even prays before he chews gum".
Danny and Mindy are co-workers with a very strong personal chemistry. Although most of Danny's interactions with Mindy are fairly antagonistic, there is often an underlying affection and tenderness that can be noted in their relationship. He has great respect for her as a doctor and as a leader (although he tries to hide it), and he often finds that she has great ideas for the workplace, something he only admits under extreme duress.
Depsite his hidden appreciation for her professional talents, he thinks her personal life is messy and all over the place and is openly critical of her decisions. He takes an active interest in her personal doings, giving her advice on her dating life (solicited and unsolicited), commenting on her outfits, her choice of men, and her behavior in general. These are comments that Mindy takes in stride; she selects the comments that suit her and discards the ones that don't.Mindy's understanding and interpretation of their relationship is possibly more intuitive than Danny's. She seems to instinctively understand that he speaks from a place of concern and caring when he interacts with her, even if his comments are often harsh and blunt. Danny, however, is somewhat in denial:
- „Danny – You and I don't have a personal relationship
Mindy – Yeah we do -- we just collaborated on this awesome card and we share an office
Danny – I share an office with lots of things; you, that lamp...
Mindy – I'm like the lamp?
Danny – I'll put it this way: I have the same personal attachment to you both”
- —Danny & Mindy[src]
In this way, Mindy is perfectly suited to dealing with Danny: she understands when it is necessary to push the issue and get him to admit his error, and when to back off and let him arrive at his own conclusions. In this case, she pushes the issue, forcing Danny to admit that he and Mindy do have a personal relationship and a close friendship. He is usually the first person to rush to her aid or to notice when something is wrong, such as the time when Mindy was punched in the nose or when Mindy found out Josh was cheating on her. In these moments, he does his best to stay close to her and comfort her, abandoning his personal plans in order to take care of her:
- Mindy – "Please go."
- Danny – "I thought my presence would be comforting."
- Mindy – "Not really."
- Danny – "No?"
- Mindy – "You have this rattle when you breathe."
- Danny – "Sorry. I-I just didn't want you to be by yourself."
- – Mindy and Danny, Season 1 "Josh and Mindy's Christmas Party."
Danny continues to be a close, comforting presence for Mindy as their friendship deepens, helping her out with various projects and devoting time and attention towards her. He also trusts her with personal information, confiding in her his relationship woes and listening to her when she gives him advice. Mindy, in turn, texts him often about happenings in her life, which he often responds to immediately.
It is interesting to note that Danny pays close attention to the details Mindy tells him and seems to have a heightened awareness when it comes to her and her interests. Her femininity complements his masculinity beautifully, and although they are opposites in many ways, their personality traits mesh to form a relationship that works very well.
At the end of 2.14 (the second season's 'Winter Finale'), Danny succumbs to his growing romantic feelings for Mindy and passionately kisses her, marking a dramatic shift in their (up until then) platonic relationship. She kisses him back. They date shortly and Danny breaks up with Mindy since he thinks that their relationship would end in a bad way just like all his past relationships.
Mindy dates other guys until Danny realizes that he really loves Mindy. At the end of season 2, Danny makes a grand gesture and they reunite at the top of the Empire State Building.
By season 3, Danny and Mindy are dating. Throughout the episodes, it is clear that Mindy is more invested in the relationship than Danny. She wants to move in together but Danny is really nervous about it. She wants to be engaged by Christmas but Danny thinks it's too early since they have only been dating for seven months although they have known each other for 3 years. By the mid-season finale, Mindy is going to San Francisco for 8 months to take a fellowship in Stanford leaving Danny in New York to finally figure out what he really wants. Now Danny and Mindy are expecting their first child together as revealed by Pete in episode No More Mr. Noishe Guy. Then he goes to see her parents in India and says he is in love with their daughter.
Although he is against marriage, his visit to India and his conversation with Mindy's parents convinced him otherwise. Mindy and Danny got engaged at the end of the fourth season premiere ('While I Was Sleeping'). Mindy gives birth to their son, Leo. After going back and forth about Mindy becoming a stay-at-home mom, they break up. They later get back together telling each other that they never stopped loving each other and sit down on the couch and in the future get married .
- Danny started working at Shulman's Women's Health Associates before Mindy and Jeremy.
- Danny likes baseball. His favorite team is the Yankees, and he listens to their games on his little radio.
- He likes boxing.
- Danny keeps an electronic keyboard in his office and is teaching himself how to play. He practices on it during the work day when he is sad or upset.
- Danny likes jazz music, Led Zepplin, Eric Clapton, and Bob Dylan. He does not listen to Rihanna.
- He refuses to do the Christmas Party playlists ever since Mindy deemed him a "party-Hitler" for putting no Rihanna on the playlist and 3 hours of Bob Dylan.
- Danny got into a fistfight with a man who wore a John Mellencamp t-shirt to a Springsteen show.
- Danny wrote a letter to his ex-wife and drew a picture of their unborn child, which he kept hidden in his desk drawer until Morgan mailed it.
- Mindy suspects that Danny's condo looks like a smoky speakeasy where old men go to complain about technology.
- Mindy and Danny share part of their route home. Sometimes they ride the subway together.
- Danny occasionally rides his bike to work.
- He has an ab roller in his office that he likes to work out on sometimes.
- Danny did not get his driver's license until he was 38; all the workers at the DMV know him because he took the test several times. Jeremy was the only other person in the office who knew where he was going.
- Danny views cars as the ultimate symbol of freedom, as they allow a man to take off whenever and wherever.
- Danny is an excellent dancer. His mother enrolled him in dance lessons when he was little, something he got into a lot of fights over.
- Danny chose to spend his Thanksgiving alone in the office, practicing on his keyboard.
- One of Danny's favorite shows is Deadliest Catch.
- Danny is skilled at building gingerbread houses and possibly has a hidden artistic streak.
- Danny likes building things with his hands. He also does not like following directions.
- Danny has read up to "Catching Fire," which is Book 2 of the Hunger Games Trilogy.
- Danny is a terrible liar and will sweat when voicing deception.
- He picked up his last girlfriend (who he nicknamed "Eyepatch") in the ER.
- Danny likes to stick to a set routine and is not overly spontaneous; he balks at performances with odd twists to them or meals scheduled at odd times.
- Danny is jealous of the fact that things come easily to Jeremy.
- Danny wept when his favorite sub-sandwich shop closed.
- Danny went to high school with some of the guys who play the song "Stomp Da Roach (Remix)"
- Danny was as stripper called Diamond Dan during med school in order to pay for school and pay off his mother's mortgage.
- He is best friends with Jeremy Reed.