Dianna Agron rewatching Naya Rivera in Glee as she struggles with loss of castmate

Dianna Agron has been rewatching episodes of Glee to help her cope with the disappearance and death of her castmate Naya Rivera.

Agron has posted a touching tribute to her late friend on Instagram, a day after Naya's body was found floating in Lake Piru, California, calling her a 'magnetic talent'.

Rivera disappeared during a boating trip with her four-year-old son, Josey, and now it has been determined she helped him to safety on their rented pontoon after they experienced difficulty while swimming. She didn't have the strength to save herself and drowned.

Dianna recalled meeting Naya on the Glee set, where they quickly became friends.

"Naya and I fell into stride with such ease, she was my first friend and ally on our show," she wrote. "In the pilot, our characters came and went with such swiftness. Our enthusiasm brimmed with all of the unknown," she recalled.

"I've been revisiting Naya's performances on our show and it has brought me great joy," Dianna continued, "To work with her was a gift. There was a great deal to absorb - her work ethic, her fearlessness, her talent - supreme."

Remembering her friend as having a 'laugh that would envelop you and hold you captive,' a twinkle in her eye, and a luminous smile, Dianna celebrated the actress saying, "Naya lead with truth, humor, wit (sic). I loved her for all of these reasons."

She added: "As I write this, I'm grinning with swelling memories of a spontenaous (sic) 36 hour excursion - one might even say diversion - to Paris. With Naya, everything was possible and would often simply unfold before us, almost magically."