The Professor met his match with unlikely ally Alicia on Money Heist.

Warning: This article contains spoilers about the final season of Money Heist.

Actress Najwa Nimri's Alicia Sierra is Money Heist's greatest gift.

Fearless, ruthless, and hilarious, Inspector Alicia Sierra bursts onto the scene when the Professor's (Álvaro Morte) gang begins their Bank of Spain heist in Part 3. Bringing with her an intense yet different energy from the other law enforcement figures on the hit Netflix show, Alicia keeps the Professor, and viewers, on their toes from the moment she appears — and keeps that momentum going through the series' end.

Unlike the heist crew, Alicia joins the Professor's team not for a glamorous life of crime, but to get out of dire circumstances. Money Heist gives Alicia one of the most transformative and unique arcs on the show, so it's no surprise that she's the absolute standout of a fantastic bunch during the Spanish series' final season.

Alicia first enters the fray with a mission to stop the Professor's gang and no moral compass. When Raquel (Itziar Ituño) joins the second heist as Lisbon, Nimri's Inspector is the team's new, formidable adversary. Early on, she proves herself to be an unrelenting opponent: she buries Rio (Miguel Herrán) alive to torture information out of him. Alicia's single-minded pursuit of the Professor causes her to lose both her job and reputation, but when she ends up with a gun pointed at the mastermind's head, she accomplishes what many could not in a season-ending cliffhanger.

The final season picks up with Alicia finding her way into the Professor's secret lair, armed with nothing but a hoodie and her gun. Not only does Alicia subdue the Professor, she manages to take down Marseille (Luka Peroš) and Benjamin (Ramón Agirre) when they return to the lair. The duel between Alicia and the Professor reaches a new level now that they are in the same physical space. Alicia poses the greater physical threat, the the Professor, the intellectual threat. But their battle in that damp, dirty bunker shows that the sum of both their skills is what makes them a perfect match. The stakes are incredibly high — the Professor has his team to think of, and Alicia her unborn baby — and their dance is fascinating to watch.

Alicia maintains the high ground until her water unexpectedly breaks in one of the most memorable scenes of the series. Her determination turns into obstinance when Alicia attempts to deliver her baby solo while her three abductees watch. Nimri's mix of dramatic and comedic talent infuses the stress, screams, cursing, and chaos with a humor that makes the scene soar. She leaves viewers worrying about the newborn while also wanting to laugh at her for dragging a dirty mattress across the room to keep an eye on her hostages while giving birth. The actress plays Alicia's stubbornness well; she refuses to let the Professor help until the baby's life is clearly in danger. The unforgettable scene marks a turning point for Alicia: she's starting to think the best option for her new family's future is actually working with the man she meant to take down.

Their new partnership results in a buddy comedy-like arc for the duo in the second half of the final season. When it looks like the Professor's team is outmatched after Tokyo's (Úrsula Corberó) death, Alicia makes a run for it, and he goes after her. Seeing them try to stay ahead of the cops together was watching two masters at work. It is the best of the Professor's adventures away from his team. Alicia's cop background and the Professor's strategic mind gets them out out alive, but it's their banter that makes this jaunt the show's best.

There isn't a more powerful testament to the show's belief in Nimri, and the Professor's belief in Alicia, than when she's tasked to find the stolen gold. To complete his plan, the Professor realizes he needs to split his people outside the bank into two groups. He puts Alicia in charge of finding their stolen gold. Stressed from the risk of getting caught, and worried about her newborn, Alicia doesn't believe she can do it without him. He's the mastermind, after all.

But the Professor's belief in Alicia is unwavering: "Interpol spent month after month looking for me all over the planet. They never found me. You did," he tells her. While she started as an adversary, the Professor has never disregarded her talent. He knows she's more competent than Colonel Luis Tamayo (Fernando Cayo) and Ángel Rubio (Fernando Soto). The scene's significance doesn't only serve as a reminder that the Professor considers Alicia an equal; it's that he trusts her to save his family.

Ultimately, the Professor's greatest gamble is successful — thanks in large part to Alicia. The winning strategy was one of teamwork: Alicia tracked down the gold, and the Professor convinced their rival criminal outfit that there wasn't enough gold to go around. In the end, Alicia rode off into a brand new life with her newborn and money in the bank — precisely what the former police inspector deserved.

Money Heist's final episodes are streaming now on Netflix.  

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