There have been many listsasking about fans' favorite characters. But what about the worst? On Grey's Anatomy, fans have seen many characters leave just as quickly as they have arrived. There are only two reasons for this: they are there to cause some drama or to set off another character's exit. Most of the time, these revolving door characters are not liked by the viewers.

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But which supporting character do you think has been the worst? From the reappearance of Denny Duquette to Nancy the rude Shepherd sibling, here are the 10 most hated supporting characters on the series, ranked.

When Denny was introduced to the show, everyone loved him. After Alex cheated on Izzie, it was nice to seeher be treated with the love and respect she deserved. Fans were devastated for the couple when Denny sadly passed away.

However, they were all confused when Ghost Denny reappeared. Although Izzie got back together with Alex, she soon began a relationship with the apparition. Fans got sick of seeing Ghost Denny as he lingered around with no explanation of how his existence was possible. Even after Izzie's tumor was diagnosed he still popped up.

The whole Ava/Alex romance was a relationship the fans detested. Ava, otherwise known as Rebecca Pope, was first introduced in Season 4 after being involved in the ferry boat accident. Alex was assigned to the case,and the two grew closer.

Ava soon came back for Alex after leaving her husband and baby. However, her presence began to affect Alex's work and personal life. In the end,he was forced to get her sectioned as she began to struggle with her new identity. Although he claimed to like her, fans never knew what happened to Ava after she was committed. It just made the storyline seem pointless.

Eliza Minnick was one of the most hated doctors to ever walk the halls of Grey Sloan. Introduced in Season 13, Minnick was brought in to replace Webber as the head of the surgical residency program. She also caught the eye of Arizona,and the two briefly started a relationship.

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However, Minnick became the enemy of many attendings when she intervened in their surgeries. She proved to be a stickler for the rules, ordering the residents and attendings to follow protocol. Fans soon rejoiced when Bailey gave Minnick her marching orders for putting Stephanie in danger.

In Season 9, the hospital was on the verge of collapse after they were forced to pay the crash settlement. As a result, Alana Cahill was brought into the hospital to help them find an investor. Similar to Minnick, Alana got on the wrong side of the attendings by trying to change the hospital procedures and administration.

She first closed the ER, which April and Derek protested against. She also placed cameras in the CCU, where a remote physician would supervise the doctors with their bedside manner and patient care. Alana cemented her enemy status among the attendings when she disapproved of them saving a trauma patient.

Out of all the Shepherd sisters, Nancy has proven to be the worst one of all. When it came to her siblings, Nancy didn't treat them with respect. She was rude, judgmental and very unsupportive of Amelia and Derek's decisions.

When Derek wanted to divorce Addison because she cheated, Nancy told him to forgive her. She refused to donate a nerve to help Derek with his hand. Unsurprisingly, Nancy treated Amelia just as badly as her other siblings, humiliating her in front of Link. It's come to the point where fans hate every moment she's onscreen.

In Season 7,Lucy Fieldswas first introduced when Arizona picked her to monitor Callie's pregnancy. Lucyalso began a relationship with Alex after the pair briefly butted heads over their patients.

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However, she cemented herself as one of the worst characters when she poached a job opportunity off of Alex. In the episode "I Will Survive," Lucy overheard Arizona offer Alex a position at the Namboze Clinic in Africa. After much debate, Alex chose to turn down the position because he was in love with Lucy. Turned out the relationship wasn't as important to the obstetrician, as she swipedit from under his nose.

Reed Adamson first made an appearance in Season 6, coming in during the Seattle Mercy-West merger. Fans took an immediate dislike to the resident after she refused to move out of George's cubby. She also butted heads often with Alex over the handling of patient care.

Other than the fact that she was April's best friend and would sleep with attendings to scrub in on surgeries, fans learned nothing else about Reed. It was hard to form an opinion when the writers didn't give her a storyline of her own. Although it was a shock, her death had no impact on the show.

Another person fans didn't take to was Penelope Blake. Penny didn't make a good impression on the fans when she was one of the doctors responsible for Derek's death. They were even more surprised when she was introduced as Callie's new girlfriend, transferring to Grey Sloan to take part in the residency program.

AlthoughPenny was nice, no one could warm up to the resident as she continued tofosterchaos. She caused a custody battle between Arizona and Callie when the ortho surgeon wanted to move with Sofia.Penny was also responsible fortensionbetween Meredith and Amelia and had her own mini-feud with Stephanie. No one was really sad to see the back of Penny.

Gary Clark has to be one of the worst villains on the show. Responsible for the deaths of many physicians, including Reed and Charles Percy, Gary was the gunman that went on a shooting spree.

At first, fans felt sympathetic towards Gary when his wife was pulled off of life support. However, they became unnerved when the grieving widower continued to show up at the hospital. The firsttime waswhen he filed a lawsuit against Derek and the hospital for 'killing his wife." The second was when he turned up brandishing a gun. No one expected this storyline would take such a sinister turn.

Although the guy had been highly respected in the medical community, Harper Avery was the absolute worst. He was disrespectful to everyone, including Jackson, whom he treated like a child and belittled about his divorce.

Harper sealed himself as the worst supporting character when the surgeons found out he had sexually assaulted hundreds of women. Everything that the Harper Avery award represented was now tainted by the revelation of the man's true self. The foundation he set up was quickly dissolved and was replaced by Catherine Fox's, who promised to help his victims heal.

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Grey's Anatomy: Most Hated Supporting Characters, Ranked - Screen Rant