Jill Riley was a fictional character from the first series of Baywatch

Baywatch

Baywatch is an American action drama series about the Los Angeles County Lifeguards who patrol the beaches of Los Angeles County, California, starring David Hasselhoff. The show ran in its original title and format from 1989 to 1999, sans the 1990-1991 season, of which it was not in production...

. She was played by Shawn Weatherly from 1989 to 1990.

Her character was the most experienced female lifeguard

Lifeguard

A lifeguard supervises the safety and rescue of swimmers, surfers, and other water sports participants such as in a swimming pool, water park, or beach. Lifeguards are strong swimmers and trained in first aid, certified in water rescue using a variety of aids and equipment depending on...

 on service, she trained Shauni McClain

Shauni McClain

Shauni McClain is a character from the TV series Baywatch from the late 1980s to early 1990s. She was played by Erika Eleniak.Shauni was a complete rookie when she started out as a lifeguard with Baywatch, being scared of people drowning and freezing up when people needed CPR...

 how to become a better lifeguard and was respected by all of her friends at Baywatch. She died from an aneurysm

Aneurysm

An aneurysm or aneurism is a localized, blood-filled balloon-like bulge in the wall of a blood vessel. Aneurysms can commonly occur in arteries at the base of the brain and an aortic aneurysm occurs in the main artery carrying blood from the left ventricle of the heart...

 caused by a shark attack during "Shark Derby", the 18th episode of the series.

Shawn Weatherly appeared in 19 episodes (including the pilot) of the first season.