Baron Frederick von Geisler (Tagalog: [ˈgaɪslɛɾ]; born June 5, 1982) is a Filipino actor and entrepreneur of German-American descent.

Geisler's performance in the 2022 Netflix film Doll House has also earned him praise from critics, audiences, and fellow actors.

A year later, he became officially a part of ABS-CBN's roster of rising homegrown talents as a member of the elite Star Circle Batch 5 (1997).

He was considered as one of the network's most promising young stars alongside John Lloyd Cruz and Marc Solis in the teen boy trio "Koolits", where he was once paired up with Kristine Hermosa.

Around this time, Geisler continued acting in supporting and teen idol roles alongside his fellow Ang TV and Star Circle co-stars, including Nagbibinata (1997), Haba-baba-doo!

In 2011, Geisler played Erning Toothpick (a character originally played by actor Paquito Diaz based on its real life counterpart, Ernesto Reyes) in the 2011 Metro Manila Film Festival entry of Viva Films, Manila Kingpin: The Asiong Salonga Story top-billed by then-Laguna Governor Jeorge "ER" Ejercito Estregan.

Geisler was part of the fantasy series Dyesebel in the same year with Anne Curtis, Sam Milby, and Gerald Anderson where he played one of the villains, the devious Kanor de la Paz.

In May 2019, after going in sabbatical for alcohol dependence recovery in Cebu, Geisler returned to acting via FPJ's Ang Probinsyano in a critically acclaimed performance where he played one of the show's villains.

[6] In 2018, Geisler joined Maranatha Christian Fellowship, a "Bible-based, spirit-led congregation" in Cebu, and speaking about mental health awareness at various symposiums.

[11] In September 2019, initial reports surfaced online saying that Geisler was conferred to the title of "Peace and Prosperity Ambassador" by Mohammadmamay Hasan Abdurajak and Maria Makiling Helen Fatima Nasaria Panolino Abdurajak allegedly from the Royal Sultanate of Sulu and North Borneo, thus making Geisler a Datu of Sulu.

[12][13] On July 19, 2024, actress Nadia Montenegro revealed on Fast Talk with Boy Abunda that Geisler is the father of her youngest daughter Sophia, who was born in 2006.

[15][18] Geisler was tagged as the "Wild Child" of Philippine showbiz, a nickname widely used in 2007 during his stint in Pinoy Big Brother: Celebrity Edition 2.

He was found guilty in 2013 and was sentenced to a minimum of six months and maximum of over two years in prison, in addition to paying ₱30,000 to Martinez for damages and community service.

According to news reports, Geisler allegedly made unwanted sexual advances towards Kurdi, groped her and masturbated in front of the actress while filming for the TV series SRO Cinemaserye.

According to a report from DZMM posted on the ABS-CBN website, the Traffic Division of Pasig said that Geisler was driving his car after his taping when he got into an accident with the truck.

[34] On May 15, 2016, Geisler again featured in a viral video showing him verbally berating a production team and assaulting a student filmmaker from the University of the Philippines.

[38] Not long after on May 25, 2016, another viral video showed Geisler being involved in a brawl with independent film actor Kiko Matos in a bar in Tomas Morato, Quezon City.

[40] Following the incident, Universal Reality Combat Championship (URCC), a mixed-martial arts promoter, announced that the two actors will participate in an exhibition MMA match on June 25, 2016.

[42] It was later revealed in December 2016 that the bar brawl between Geisler and Matos was staged performance art for a documentary called Beastmode: A Social Experiment.

[52] Prior to the incident, Geisler also had a standing arrest warrant issued in Cebu for smoking inside a plane, in violation of the Civil Aviation Authority Act.