John Sessions, best known for his TV appearances on “Whose Line Is It Anyway?” and “Splitting Image,” is dead at 67. The actor’s agent Alex Irwin has confirmed that Sessions passed away at his home in South London on Monday after a heart attack. Tributes are pouring in on social media from his friends and fans, remembering him as a “towering intellect,” “incredible performer” with “true talent,” and all around “lovely” man.