THEION

Captain - Marianthi Kasdagli
Marianthi is a highly experienced and capable captain, known for her deep knowledge of navigation and ability to handle challenging situations at sea with confidence and precision. She holds a Class A’ Diploma from the Merchant Marine Academy of Macedonia and she has built a distinguished career in the superyacht industry, earning a reputation for precision and operational excellence across a diverse fleet of high-profile yachts. Before joining M/Y Theion in 2026, she commanded luxury yachts including M/Y LIBERDADE, M/Y ALMAHA, M/Y PARVATI, M/Y SANTORINI, M/Y FOS, as well as the mega yacht ELYSIUM. With extensive cruising experience throughout Greece, she possesses in-depth knowledge of Greek waters. Her strong understanding of local weather patterns, port infrastructure, and secluded anchorages enables her to design efficient and highly tailored itineraries, delivering both operational confidence and unique guest experiences while maintaining high standards of safety. In her free time, she is passionate about sports, particularly swimming where she has been recognized as a champion and she enjoys maintaining a high level of physical fitness.


Engineer – Konstantinos Syrigos
Konstantinos was born in 1977 and he is a Greek national. He is a graduate of Merchant Marine Academy of Aspropyrgos and he holds all necessary certificates for his position. He started his career onboard tanker ships, transitioned to passenger ships and entered yachting industry in 2019. Before joining M/Y Theion, he was onboard various yachts such as M/Y Alexander, M/Y Dana, M/Y ALL Seven. With a strong background in marine engineering and a commitment to safety and reliability, Konstantinos ensures all technical aspects of the yacht’s function at optimal performance, allowing smooth, uninterrupted cruising. Konstantinos speaks English and enjoys fishing and travelling.


Chef – Giannis Avlonitis
Chef Giannis is a creative and results-driven chef with international experience across luxury yachts, Michelin-starred restaurants, and fine dining establishments. He is a graduate of Le Monde, Culinary School and he is an expert in Mediterranean, Greek, Italian, and Asian cuisines, with strengths in menu design, food presentation, and kitchen leadership. He has collaborated with the Executive Chef Kostas Akouros (2023–2025), he has served as Private Chef on M/Y SATORI and M/Y DANA and held key roles at The Whitebrook (1 Michelin Star, Wales), Chez Michel (Athens), Fino Santorini, Boho Miami, and Cookoovaya (Athens). Giannis was also a semi-finalist (2021) at MasterChef Greece (reality show), known for delivering high-quality, innovative culinary experiences in diverse, high-pressure environments. Giannis speaks English and enjoys travelling.


Stewardess – Eugenia Xenou
Eugenia is a highly experienced yacht stewardess with over a decade of service aboard both charter and private yachts ranging from 30 to 70 meters. She is serving on board M/Y Theion since March 2023, where she oversees the full scope of interior operations, including high-end guest service, detailed housekeeping, laundry care, and refined table settings—all executed with professionalism, discretion, and a strong eye for detail. Before joining M/Y Theion, she served aboard M/Y Duke, M/Y Riva I and M/Y Karma further developing her ability to deliver five-star service in fast-paced charter environments. From 2015 to 2020, Eugenia held a long-term position aboard the 70-meter private yacht M/Y Astarte, where she enhanced her professional skills in luxury service, VIP guest care, and interior team coordination. Her previous roles on M/Y Christina V and M/Y Silly contributed to her well-rounded expertise and adaptability across different yacht programs. With a calm presence under pressure, exacting standards, and a passion for ensuring a smooth and hospitable environment, Eugenia consistently proves to be a dependable and integral part of the interior crew. She speaks English and enjoys reading books.


Deckhand – Ansar Adeel
Ansar is an experienced sailor with over 15 years working on charter yachts. He has been serving onboard M/Y Theion since 2022. He is responsible for daily deck operations, maintenance, and supporting safe navigation. Previously worked on M/Y Dana from 2017 to 2022 and M/Y Cosmos 2 from 2008 to 2017. Reliable, hardworking, and dedicated to maintaining high standards of vessel upkeep and guest safety. He speaks English and loves water sports.