Actor James Darren, known for his work in films like Gidget and TV shows such as T.J. Hooker and Star Trek: Deep Space Nine, has passed away at the age of 88. TMZ reported that the veteran performer died peacefully in his sleep at Cedars-Sinai Hospital in Los Angeles on Monday.

The exact cause of Darren’s death is currently unknown. However, the actor’s son, Jim Moret, reportedly shared with TMZ that his father had been experiencing heart issues and was a patient in the cardiac unit at Cedars-Sinai. Darren had initially gone to the hospital for an aortic valve replacement but was deemed too weak to safely undergo the procedure. After being sent home, he returned to the hospital shortly thereafter.

Jim Moret expressed his disbelief, stating, “I always thought he would pull through because he was so cool. He was always cool.”

Darren rose to fame as a teen idol after portraying the character Moondoggie in the 1959 film Gidget. He continued the role in the sequels Gidget Goes Hawaiian and Gidget Goes to Rome. Darren also had a recurring role as police officer Jim Corrigan on T.J. Hooker, appearing in 66 episodes over four seasons.

In addition to his acting career, Darren was also a singer and performed the theme song for Gidget. He later directed episodes of popular TV shows like Melrose Place, Beverly Hills, 90210, and The A-Team.

Rest in peace, James Darren.