Howard Hawks once said that a good movie has three strong scenes and no weak ones. Suddenly, Last Summer features four very effective scenes largely carried by one of the two major actresses in the lead roles—or, on occasion, both. These are extended sequences, but they never feel dull; you remain completely engaged, captivated by what’s unfolding onscreen. Katharine Hepburn and Elizabeth Taylor deliver distinct, even contrasting performances – Hepburn as a wealthy, elderly woman who pretends to be of sound mind, and Taylor as a young woman labeled “violent” despite being seemingly rational – yet the combined effect is undeniably powerful: it's impossible to take your eyes off Taylor, and you can’t look away from Hepburn (reportedly, after her scenes were completed, Hepburn showed her disapproval of director Joseph L. Mankiewicz and producer Sam Spiegel by spitting in their faces). The focus remains on these two women—much like the other characters, who are essentially extras, the actors portraying them being fortunate members of a VIP audience watching a pair of acting greats at close range. However, another figure looms large over everything: Sebastian Venable, Hepburn’s son and Taylor’s cousin, whose hidden homosexuality Hepburn attempts to conceal by arranging for Taylor to undergo lobotomy performed by Montgomery Clift's neurosurgeon. Since he died before the events depicted in the film, Sebastian is frequently referenced but never appears directly except in brief glimpses during Taylor’s recollections of that fateful summer. This isn’t a poor scene; it's a good one with some flaws. It doesn’t function as a traditional flashback with narration, but rather as a monologue accompanied by visuals that seem superfluous—they aren’t present in Tennessee Williams’s original play and ultimately diminish the performances. The actress playing the part should be capable of conjuring those images through her words and expressions; Liz certainly was able to do so. Furthermore, there are a few details within the flashbacks that don't quite add up; for instance, a skeleton transforms into an elderly woman in the subsequent shot—presumably intended to represent the character’s memories, but she doesn’t acknowledge it, nor would anyone listening have any way of knowing it was even there. The question then becomes: why is it included? Is Mankiewicz trying to convey something about her unconscious thoughts? And if so, what exactly? Or perhaps he was unconsciously—and thankfully, unsuccessfully—trying to undermine the film himself? I wouldn’t be surprised by that from a Mankiewicz.

Source on TMDB