Warning! Spoilers for Sirens ahead!

Sirens hints at the ages of its characters, allowing us to compare and contrast this detail with the actors who play them. The Netflix series revolves around two sisters, the youngest of whom essentially cut off her family when she accepted a personal assistant position to a millionaire philanthropist. This sister, Simone (Milly Alcock), immediately fell under the spell of her bizarrely alluring boss, Michaela Kell (Julianne Moore), making older sister Devon (Meghann Fahy) immensely uncomfortable. Of course, nothing in Sirens is exactly how it seems.

Though Sirens doesn't reveal the ages of its characters, their respective stages in life are profoundly important to their stories. Simone is a very young woman just getting started in the world, which means she is impressionable and far more susceptible to either negative or positive influence. One way or another, her connection to the much older Kells is inappropriate, and this is something that Devon picks up on. Sirens' Devon is older than Simone, but still stunted in her development since her entire focus has been on her family. So, how do the actors who portray these characters compare?

Simone Is 25 Years Old In Sirens

Milly Alcock Was 24 Years Old While Filming Sirens

Simone's age isn't explicitly stated in Sirens. However, we know that she is old enough to have completed her undergraduate degree as well as a year or so of law school. Simone ultimately dropped out of school to become Michaela's assistant, and it's implied that she had held this job for less than a year by the start of Sirens season 1. Still, the most significant clue regarding Simone's age comes from her conversation with Devon about the years that have ed since high school.

Filming for Sirens began in June/July 2024 and concluded in the fall of that year.

Eventually, in Sirens, Simone mentions to Devon that she has been out of high school for seven years. Assuming that Simone was 18 when she graduated from high school, this would make her about 25 in Sirens. Actor Milly Alcock was born on April 11, 2000, which means she would have been newly 24 when filming started in June 2024. This means that Alcock's age lines up, more or less, with that of her Sirens character.

Devon Is 30 Years Old In Sirens

Meghann Fahy Was 34 Years Old While Filming Sirens

Devon is the oldest DeWitt sister in Sirens, and, like with Simone, the Netflix miniseries didn't explicitly share her age. However, since we know that Simone was about 25, we can take a guess at Devon's age as well. Simone told Michaela that she had been seven years old when her mother died, and that Devon had been 12. This places the sisters at five years apart in age, so Devon would be about 30 during the events of Sirens. However, this does somewhat contradict a comment made by Devon later in Sirens.

Throughout all five episodes of Sirens, Devon is in constant with her boss and sometimes-boyfriend Raymond, and it's noted that the pair were prom king and queen back in the day. Raymond has had a hard time letting the good old days go, and frequently mentions his and Devon's golden years in high school. This ultimately leads Devon to point out that it's not "2009" anymore, implying that this is when they graduated. However, if this is true, Devon would be about 33 in Sirens, not 30. We can assume, based on this, that the series isn't set in 2025, but in 2022.

Actor Meghann Fahy was born on April 25, 1990. Since filming started in June 2024, this would make Fahy 34 years old when she shot the series—a few years older than her on-screen character. Regardless, Devon's age is significant in Sirens since it's evident that she isn't where she should be in life by her 30s. Her obsessive desire to care for her family has held her back.

Michaela Is About 55 Years Old In Sirens

Julianne Moore Was 63 Years Old While Filming Sirens

Michaela is a generally mysterious character in Sirens, so its no surprise that her age isn't revealed. However, it's heavily implied that she is significantly younger than her husband Peter. Peter left his first wife for Michaela—a successful lawyer at the time—13 years prior to the start of Sirens. He likely did this for the same reason he left Micheala for Simone. The older man wanted a younger wife to make him feel young and to give him another child.

Based on this information, actor Julianne Moore's age, and actor Kevin Bacon's age, we can assume that Michaela was about 42 when she first met Peter—not too old to potentially have a child, but old enough that getting pregnant could have presented challenges. This would make the Sirens character about 55 during the Labor Day weekend that the series is set.

Moore is only three years younger than Bacon, and though this could have been true for their Sirens character, it doesn't quite make sense with the story.

This is about eight years younger than Moore's age during filming. The actor was born on December 3, 1960, which would have made her 63 in June 2024. Moore is only three years younger than Bacon, and though this could have been true for their Sirens character, it doesn't quite make sense with the story. It's more likely that Moore's character is meant to be a touch younger than the actor herself.

Peter Is About 65 Years Old In Sirens

Kevin Bacon Was 66 Years Old While Filming Sirens

Peter Kell struggles with his age throughout Sirens, though the exact number isn't mentioned in the series. The millionaire is suffering under the knowledge of how time has flown by, ultimately blaming Michaela for the fact that he missed so much time with his children since they resented him for leaving their mother. Peter did this in the first place out of a desire to feel younger and have more children, which is precisely why he leaves Michaela for Simone at the end of Sirens. He stated that he hoped to have another with the 28-year-old, but Michaela called out that this wouldn't actually make Peter any younger.

Kevin Bacon was born on July 8, 1958, which means he was 65 when he started filming Sirens in June, and likely celebrated his birthday before they wrapped later that year. It would make sense within the context of Sirens for Bacon's character to be about the same age during the events of the series. The only problem is that Moore and Bacon are only a few years apart in age, while Moore's character is implied to be significantly younger. Bacon couldn't for any older than 65, but Moore can easily for younger in Sirens.