Watch The West Wing cast pay tribute to late costars John Spencer and Kathryn Joosten

The West Wing cast has reunited for EW's new September cover story ahead of their upcoming HBO Max special, but unfortunately not all of the actors from the show are still around today. John Spencer, who played the wise chief of staff to President Jed Bartlet (Martin Sheen), died in 2005 before the end of the show's final season, while Kathryn Joosten, who played the president's secretary Mrs. Landingham, died in 2012 at the age of 72. In the video above, you can watch The West Wing actors and creator Aaron Sorkin remember what Spencer and Joosten brought to the show.

Just as Leo McGarry acted as a mentor to the younger members of the fictional Bartlet administration, so did Spencer mentor the junior actors on set. Bradley Whitford describes him as a "mentor."

"I never got tired of watching John do more with three words than most actors could do in three scenes," says Rob Lowe. Recalling Spencer's ever-changing delivery of the line, "Thank you, Mr. President," Lowe added, "he could make that mean 5,000 different things."

Spencer could give serious acting advice, but also brought a spirit of levity to the set.

"Anytime we had anything special or unique happen, you would look over at John and he'd have this big smile on his face saying, 'this wouldn't happen if we were on a cop show!'" Dulé Hill says. "That still, to this day, sticks with me."

Mrs. Landingham was killed off in season 2 of The West Wing, inspiring one of the show's most iconic moments (Bartlet's angry monologue at God about the cosmic unfairness of her death). But both Lowe and Richard Schiff credit one of Joosten's own scenes, where Mrs. Landingham told Hill's character, Charlie, about how her sons died in war, as a high point of the series.

"That is such a masterclass in acting," Schiff says.

Watch the video above, and keep your eyes peeled for more stories from EW's The West Wing reunion.

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