Garry Shandling wasn’t easy to classify in life. He was a widely admired stand-up comic and a creator of two influential TV series: “It’s Garry Shandling’s Show,” a self-aware deconstruction of the sitcom form, and “The Larry Sanders Show,” a blistering behind-the-scenes look at a fictional late-night program.

But he was more closely associated with a certain comedic tone — a relentless self-scrutiny that he passed off as self-absorption — than with any particular gag or punch line.

When Mr. Shandling died of pulmonary thrombosis in 2016 at the age of 66, it shocked fans and fellow comedians who had looked up to him, few of whom had known that he had been experiencing health problems. He had no spouse and no children, and it was not clear who would look after his legacy, let alone what that legacy might be.

For a memorial service, Judd Apatow, the filmmaker and producer (“Knocked Up,” “The 40-Year-Old Virgin”) and one of Mr. Shandling’s many disciples, immersed himself in his mentor’s past stand-up routines and interviews, which he edited into montages. After listening to other friends and comedians reflect on Mr. Shandling at the service, Mr. Apatow became convinced there was still much more of a story to tell about him and his impact.