A wide variety of crimes plague modern society, despite how hard we collectively try to abolish them for good. Although, certain offenses — sexual assault, child abuse, and the like — are especially gruesome and frustratingly prevalent, meaning they require a special team of individuals to investigate them and bring those responsible to justice. Those are the kinds of public servants that “Law & Order: Special Victims Unit” highlights each and every week, giving audiences a look at what their job entails and the types of struggles they face, albeit in a dramatized setting.

“Law & Order: SVU” has become a small screen staple over the past 20-plus years that it has occupied NBC’s programming lineup.

People can’t get enough of Detective Olivia Benson (Mariska Hargitay) and Detective Elliot Stabler (Christopher Meloni), who recently returned from a hiatus away from the show. As a result, the series has extended long past the 500 episode mark and is currently enjoying its 23rd season, and given how popular it remains, we’re unlikely to see “SVU” disappear from the small screen for quite a while.

There’s something cathartic about seeing Benson and Stabler put the worst of the worst behind bars, but “SVU” isn’t exactly all sunshine and rainbows. In fact, it can sometimes be a rather depressing watch — particularly the installments where death looms large over the story. In the context of Season 21 specifically, this death stands out as the saddest of them all.

Ed Tucker’s death was steeped in tragedy

Just over halfway through “Law & Order: SVU” Season 21, the episode titled “The Longest Night Of Rain” hit the airwaves. It hosts the retirement of series staple Ed Tucker (Robert John Burke), who comes under fire early on for previously ignoring claims by officer Rachel Wilson (Holly Robinson Peete) that former officer Gary Wald (Michael Gaston) had forced himself on her.

Ridden with guilt, Tucker goes undercover to get a confession out of Wald and secure justice for Wilson. He successfully does so, but what happened next was both heart-wrenching and shocking.

After apprehending Wald, Tucker pulled Olivia Benson aside to reconcile and share that he’d been diagnosed with brain cancer and didn’t have long to live. To make this revelation even sadder, it likely came about as a byproduct of his time combing the wreckage of the World Trade Center for survivors after the September 11, 2001 attack. Shortly after this interaction, Tucker committed suicide and left a note for his wife Patty (Abby Royle). In it, he gave her everything he owned and confessed that he made the choice he did so that she didn’t have to spend the best years of her life taking care of him.

While Ed Tucker’s death might not have struck the right chord with a decent chunk of the “SVU” fandom, there’s no denying the layers of tragedy that surround his demise. Not only did he end up taking his own life, but the fact that he likely wound up with cancer for helping save lives during a national catastrophe is incredibly disheartening. For those reasons, Tucker’s death stands out as the single saddest of Season 21.