The TV series 21 Jump Street followed a group of young officers that often went undercover in high schools to bust drug dealers, help students, and ran into complicated situations. The 1980s show covered a lot of serious topics, from AIDS to abuse to the consequences of drugs and criminal activity. The series tackled both serious issues and lighthearted topics and provided an ample amount of relatable content for audiences.

RELATED: 10 Best Channing Tatum Movies (According To Rotten Tomatoes) 

Certain episodes, however, stand out more than others, given their content and the plots surrounding fan favorite characters. Fans certainly remember things like time Hanson learned an important lesson while in juvenile hall, and the Season 1 episode in which Sherilyn Fenn guest-starred as an abused teenager.

"Mean Streets And Pastel Houses" (8.0)

Hanson with another guy leaning against a wall in 21 Jump Street

In the season one finale, Hanson changes up his look and attitude in order to infiltrate suburban gangs that have been causing plenty of destruction and seriously hurting one another. While undercover, Hanson befriends Brian, a good kid caught in the middle who doesn't know how to get out of the gang.

While Hanson does help him stand up to Lancer, Brian still has to be arrested, which Hanson regrets. Jason Priestley of Beverly Hills, 90210 makes an appearance as one of the gang members.

"Loc'd Out: Part 1" (8.0)

Ioki talking with a man in the background in 21 Jump Street

There have been too many drive-by shootings between two different gangs as of late, and the 21 Jump Street gang is on the case. However, the case takes a disastrous turn when Ioki is shot in the first half of the two-part episode, and a hit is ordered on Hoffs as well.

Hanson, undercover with a gang, manages to fake the hit on Hoffs, but as he keeps investigating, he finds that there's a dirty cop involved, further complicating the case.

"Hell Week" (8.0)

Hanson and Ioki with several college pledges in 21 Jump Street

Hanson and Ioki go undercover as pledges for a fraternity on a college campus in order to investigate the rape of a girl that took place there. While undercover, they are exposed to the brutal reality of being pledges, as they are forced to undergo several trials, including going up a ladder and taking a drink on each step, and even finding a way to unbind themselves after they're pushed down water slides and land in the pool.

RELATED: 21 Jump Street: Brie Larson's 10 Funniest Scenes 

They save a fellow pledge from drowning and manage to uncover evidence of the rape, ending the fraternity's horrible shenanigans. Elsewhere, the brother of the girl who was assaulted tries to find his own evidence against the fraternity.

"2245" (8.0)

Ronnie in a jail cell, with Hanson in the background in 21 Jump Street

This sad episode shows Ronnie Seebok in prison, specifically on death row. Hanson tries to get Ronnie to consider making a video discouraging others from following a life of crime, but Ronnie refuses.

The episode shows audiences who Ronnie was prior to landing in jail, and what exactly led to him ending up on death row, including the murder of a cop. Ronnie ends up asking Hanson to witness his execution, ending the episode on a sad note as Hanson keeps his promise to Ronnie to be there.

"Nemesis" (8.1)

Booker with his girlfriend in 21 Jump Street

Booker is initially in a therapist's office, and he begins recounting his latest case. As it turns out, the case was a brutal one. While trying to bust a group of kids for using and dealing drugs, one of the kids is killed for allegedly being a "narc."

While Booker's guilt grows over the kid's death, he also has a cover to maintain and he begins spiraling downwards quickly. His investigation comes to a tragic halt when he discovers who the killer is and that the killer had discovered that he was actually the "narc."

"Blindsided" (8.1)

Sherilyn Fenn in 21 Jump Street

While undercover to bust some drug dealers, Hanson is also approached by a teenage girl, Diane (played by Sherilyn Fenn of Twin Peaks), and she asks him if he'll murder her father if she gives him all the money she has. Stunned, Hanson tries to talk her out of it, but it turns out that there's more to the situation than initially meets the eye, as her father sexually abuses her, and is also a high-ranking and well-known cop.

RELATED: 23 Jump Street: 5 Reasons It Should Get Made (& 5 Why It Shouldn't) 

Unsure as to what to do, Hanson consults with Penhall, and later Captain Fuller. Though they formulate a plan, it doesn't make things turn out the way they had hoped it would.

"I'm Okay, You Need Work" (8.1)

Hanson frowning in 21 Jump Street

Kenny, a boy Hanson knows from a previous case, is forced into a private alcohol and drug rehabilitation program for teenagers. Kenny mentions in his letters to his family that the teens inside are being terribly mistreated, and Kenny's sister brings his allegations to Hanson's attention. Hanson opts to take a vacation and decides to go undercover and see for himself just what's going on.

While Hanson's situation gets worse and worse on the inside, his friends begin looking for him, leading to the true nature of the horrible treatment of the teens, and the truth of what really happened to Kenny after he tried to escape. Christina Applegate also makes an appearance, playing one of the teens in the program.

"A Big Disease With A Little Name" (8.3)

Hanson looking sad in 21 Jump Street

This memorable episode finds Hanson protecting a teenage boy named Harley, who has AIDS, and who is in danger because of parents and students who don't want him attending school. Harley is struggling big time, as people are afraid to touch him and be near him; even his own parents struggle with Harley's disease.

Hanson ends up becoming Harley's only friend, bonding with him over motorcycles, and listening to the boy's real feelings concerning his disease. Hanson is there when Harley needs him most, and when Hanson later learns that Harley has died, he's clearly distraught by the news.

"Orpheus 3.3" (8.5)

Johnny Depp looking angry in 21 Jump Street

In this riveting second season episode, Hanson is considering breaking up with his girlfriend and is short with her all the way up until they head into a convenience store. There, tragedy strikes as a burglar appears at the establishment and winds up shooting Hanson's girlfriend dead before his eyes.

RELATED: 21 Wild Details Behind The Making Of 21 Jump Street  

Now wracked with guilt, Hanson is obsessed with finding her killer, and frequently watches the surveillance video of the murder over and over again, concerning his friends.

"Swallowed Alive" (8.5)

Johnny Depp pondering something as he looks down in 21 Jump Street

Hanson, Ioki, Penhall, and Booker go undercover in juvenile hall to investigate the death of one of its inmates, as well as discover the origin of drugs in the facility. Penhall, who was paired with Hanson, soon succumbs to claustrophobia, leaving Hanson on his own, as Ioki and Booker are elsewhere in juvenile lock-up.

While investigating, Hanson gets a big dose of the reality of life behind bars, and it has an impact on him, affecting him in a way he didn't expect, as he has never before been exposed to what happens to the people he arrests after they're sent to jail.

NEXT: The 5 Best (& 5 Worst) Movies Based On TV Shows