Zitto Kazann, who played the Gypsy man who told Angel about his curse in Becoming (Part 1), played the same part in the Angel episode ‘Darla’. He was in Waterworld, a movie which was script-doctored by Joss Whedon.

Jack McGee, who played Doug Perren (the curator at the museum in Becoming (Part 1)), has also appeared in Legally Blonde 2: Red, White & Blonde, Malevolent, Man Who Wasn’t There, The, Coyote Ugly, The Flintstones in Viva Rock Vegas, The Out-of-Towners, Showgirls, Basic Instinct, Backdraft, The Doors, Born …

Richard Riehle, who played Buffy’s first watcher in Becoming (Part 1), has had a long career. He was in Fear and Loathing in Las Vegas, Casino and The Fugitive. He has been TV shows such as in ER, The West Wing, Sabrina, the Teenage Witch, Star Trek: Voyager, Diagnosis Murder, …

In Becoming (Part 1), we see Buffy kill her first vampire in a flashback to when she was in L.A. Buffy misses the heart on her first try. She tells this story to Dawn in Lessons.

In Becoming (Part 1), Principal Snyder chaleenges Buffy to give him a reason to kick her out of school - he expels her in the very next episode.

Buffy fights Angel in the cemetery in Becoming (Part 1), then realises that she was distracted away from the library so that Drusilla could hurt her friends. In When She Was Bad, the Master’s lackeys used the same trick on Buffy to capture Willow for the resurrection ritual. Angelus says …

A few people have written to me saying they thought the Claddagh ring was gold in Becoming (Part 1), not silver as it was in Surprise. I’ve checked it out, and I think it’s just the way the light falls on the ring, rather than the fact that the ring …

The scene where Darla sires Angel was first alluded to in the episode Angel. We see the scene in a flashback for the first time in Becoming (Part 1). Angel was sired in 1753 in Galway, Ireland.

In the episode Angel, it appeared to be established that the restoration of Angel’s soul took place sixty years ago, or sometime in the 1920s. However, in Becoming (Part 1) it’s revealed to have taken place in 1898.

When Becoming (Part 1) was repeated on September 15, 1998, it was presented with a different first scene. There were several differences, but the most notable was that Max Perlich (Whistler) provides the voice-over for that scene, rather than David Boreanaz.

Buffy’s first watcher, shown in a flashback in Becoming (Part 1), was played by Richard Riehle. His name isn’t mentioned, but the Season Two Script Book clarifies that his name is Merrick. In the Buffy movie, Buffy’s first watcher was called Merrick, played (hammily) by Donald Sutherland.

Steven Spielberg’s 1975 shark movie Jaws is alluded to a few times in Buffy.
In Go Fish, Xander says, “This was no boating accident” - which is a line from the first Jaws movie.
In Graduation Day (Part 1), Xander and Giles open a page of a book to see a …

In Go Fish, Willow says Oreo cookies have “chocolately-goodness”. This may be an in-joke as she once did a commercial for Oreo.

The band Twisted Sister is mentioned in Go Fish (Gage calls Buffy a “Twisted Sister”). Mark Metcalf, who played the Master, played the father in Twisted Sister’s “We’re Not Gonna Take It” video.

There’s some discussion in Go Fish that Angel can’t drink the blood of the swim team as it’s contaminated. This is first shown in School Hard when Spike talks about being at Woodstock and drinking from a drugged hippy there.